Shortly after the completion of Operation BIRMINGHAM in May 1966, General William C. Westmoreland, Commander, U.S. Military Assistance Command, Vietnam, directed Lieutenant General Jonathan O. Seaman, Commanding General, II Field Force, Vietnam, to plan an operation for War Zone C in northern Tay Ninh Province to start soon after the Christmas and New Year stand downs of 1966- 67. He further indicated that it should be a "big operation." Over the next several months the operation, to be known as JUNCTION CITY, was planned. As approved by General Westmoreland, the operation was to start on 8 January 1967, was to be multidivisional, and was to include a parachute assault. The operation to commence on 8 January would not be JUNTION CITY: the preemptor was to be known as CEDAR FALLS.
As II Field Force troop strength built up in 1966 and it became more capable of attacking the enemy in longtime havens, General Seaman's headquarters was considering the possibility of a powerful strike into the Iron Triangle. The Iron Triangle is generally defined on the southwest by the Saigon River, on the east by the Thi Tinh River, and on the north by a line running west from Ben Cat to the town of Ben Suc on the Saigon River. To the north lies the Thanh Dien Forestry Reserve. The Iron Triangle has been characterized as a dagger pointed at Saigon and, being only twenty kilometers away, was the enemy's largest haven close to that city. The area was heavily fortified and known to contain the Viet Cong headquarters for Military Region IV which directed military, political, and terrorist activities in the Saigon-Gia Dinh capital region complex. Viet Cong control of the Iron Triangle permitted the enemy forces to dominate key transportation routes in the surrounding area. This important center for controlling and supporting enemy operations had to be attacked decisively and in force if the attack were to succeed in rupturing and neutralizing the control structure.
At a planning meeting in September 1966 General Seaman discussed the possibility of an operation in the triangle with General Westmoreland, who suggested a coordinated operation with forces on both sides of the Saigon River. He envisioned troops moving into position on one side of the river to form an anvil followed by a rapid move from the other side to hammer the enemy against the anvil. Discussion also turned to the need for extensive clearing to strip the area and deprive the enemy of concealment. By November General Seaman's headquarters was planning not only for Operation Junction City but also for Cedar Falls. Intelligence collection was directed at both operations.
A new approach to assigning intelligence collection responsibilities in III Corps had been taken with the publication of a II Field Force, Vietnam, intelligence collection plan. The plan assigned specific intelligence collection areas, tasks, and responsibilities to U.S. and allied units within the III Corps area; the objective was a closely integrated and coordinated effort by U.S. and allied agencies. Unit collection responsibilities were assigned on the basis of geographic areas. Close liaison was effected between U.S. and allied units from division through battalion level and between U.S. advisers and corresponding commanders of South Vietnamese Army units or province and district chiefs. The plan was designed to provide for the collection of maximum information with minimum duplication of effort.
A step was also taken to improve the intelligence collection effort through the establishment of a source control program in the III Corps area. When fully implemented, this program administratively controlled and identified confidential informants and sources, assisted in their evaluation, prevented utilization of each source by more than one agency and avoided employment of unreliable agents.
Operation Cedar Falls was the first large scale operation to benefit from "pattern activity analysis," a system begun in mid 1966. This procedure consisted of detailed plotting on maps of information on enemy activity obtained from a variety of sources over an extended period of time. As more data were plotted, patterns of activity and locations emerged. It thereby became possible to focus prime attention on those areas of intensive or unusual activity.
Aerial observation and photography, sensors, patrol reports, infrared devices, sampan traffic counts, enemy probes of Regional and Popular Forces posts, agent reports, civilian movement reports, reports of increased antiaircraft fire, disclosures of caches (and the amount and nature of the material in them), and captured documents-these sources and more revealed much about enemy intentions. Increases in road ambushes or bridge destruction usually meant that the Viet Cong intended to attack in a location where denial of the roads would aid the enemy. Some idea of the enemy's intent could be determined by checking even the amount of wood shipped into an area for making caskets or the number of civilians impressed as porters. The extent and nature of the enemy's own intelligence gathering revealed much about his intentions and even the size of the operation he was planning.
Detailed plotting of all this information and careful analysis of the patterns enabled U.S. forces to launch spoiling attacks both with ground troops and with massive air strikes. Where no pronounced pattern developed in an area, efforts were concentrated elsewhere, thereby conserving forces. Pattern activity analysis was invaluable in developing broad long-range direction of military operations, while at lower echelons it provided commanders a basis for planning day-by-day operations.
The excellence of the intelligence effort was vividly demonstrated by the results achieved. A comparison of installations discovered during Operation CEDAR FALLS with order-of-battle intelligence holdings collected before the operation disclosed a high degree of correlation. For example, of 177 separate enemy facilities found by the 11th Armored Cavalry Regiment, 156, or 88.1 percent, were located within 500 meters of the locations previously reported. The average distance was about 200 meters.
Intelligence information prompted General Seaman to recommend that Operation CEDAR FALLS precede Junction City. General Seaman related the events surrounding the change as follows:
In early December, if I recall correctly, I received a telephone call from [Brigadier] General [Joseph A.] McChristian, (Assistant Chief of Staff, Intelligence [J-2], MACV) saying that he would like to come out and brief me on some intelligence information he had concerning the III Corps Tactical Zone. He came out with several young MI (Military Intelligence) lieutenants who had been in some building in Saigon poring over (special) research reports, clandestine reports, and everything else available. The briefing lasted a couple of hours and was a most convincing presentation in that they had a pretty good idea where Military Region IV headquarters was, plus some of the support elements of Military Region IV. General McChristian said he wanted to bring this to my attention for whatever I felt should be done. I did a lot of thinking about all this and was convinced that he had some good solid, sound information. I called my staff in and told them to prepare plans for an operation to seal off the southwest side of the Saigon River and the Iron Triangle with the objective of seeing what we could find with respect to Military Region IV. We came up with a plan of operation that, to me, was pretty sound. I asked General Westmoreland to come to my headquarters so that I could brief him on a concept of operations for "Cedar Falls." We had developed a good cover plan so that we wouldn't compromise the operation. I was going to propose to him that we postpone "Junction City" for two main reasons.
First, I felt that the intelligence information we received from General McChristian and his people was so good that we had to capitalize on it. Secondly, the 9th Division was on its way from Fort Riley and would arrive in theater in December and early January.
So, I felt that if we postponed "Junction City" for a month or a little more, this would give me another division I could use to take over some of the other missions that were going on. Remember, we didn't conduct just one operation at a time. . . . With those two facts in mind; intelligence, and that the 9th Division was on its way over, I felt that there was a great advantage in postponing "Junction City."
General Westmoreland was briefed on CEDAR FALLS; the advantages and disadvantages were weighed and the decision made: Operation CEDAR FALLS, rather than JUNCTION CITY, would begin on 8 January 1967. The mission: II Field Force, Vietnam, attacks the Iron Triangle and the Thanh Dien Forestry Reserve to destroy enemy forces, infrastructure, installations, and Military Region IV headquarters; evacuates civilian population; and establishes the Iron Triangle as a specified strike zone to preclude its further use as a support base for Viet Cong operations.
General Seaman furnished further planning guidance: the Iron Triangle area was to be attacked violently and decisively with all forces available in a "hammer and anvil" operation. Deceptive deployments on seemingly routine operations would preposition the forces. The anvil would be positioned first and the hammer then swung through the Iron Triangle. The objective area was to be sealed tightly throughout the operation to prevent enemy escape. The triangle itself was to be scoured for enemy installations, cleared of all civilians, stripped of concealment, and declared a specified strike zone. The destruction of the enemy's Military Region IV headquarters was the principal objective of the operation.
In addition to the Military Region IV headquarters, the other Viet Cong units in the area were suspected to be the 272d Regiment, the 1st and 7th Battalions of Military Region IV under the 165th Viet Cong Regiment, the Phu Loi Local Force Battalion, plus three local force companies. (Although the suspected location of the 272d Regiment presented a threat during the initial stages of the operation, this unit displaced to the north as the operation progressed.) Other intelligence sources indicated the 2d, 3d, and 8th Battalions of the 165th Viet Cong Regiment might also be encountered.
The Thanh Dien forest and the Iron Triangle were known to contain strongly fortified positions with the routes of approach mined and booby trapped. The terrain in the area consists of dense forests and wet, open rice lands. Cover in the rice paddies, marshes, and swamps is generally limited to road embankments and dikes. Fields of fire are poor in the forests. Vehicle movement is restricted to existing roads and some trails. What few slopes exist are very gentle; the highest points in the area do not exceed forty meters.
The weather for Cedar Falls was most favorable during January when the northeast monsoon develops to its fullest, leaving the interior regions of the III Corps area with relatively clear skies and little precipitation. Except for periods of early morning fog and occasional morning and afternoon rain showers, cloud ceilings are unlimited and the visibility is excellent. The temperature varies from a low of 59 � to a high of 95 �.
The deception planned in positioning the various units was involved and critical. The 11th Armored Cavalry Regiment was to come from Xuan Loc, 100 kilometers to the east, and the 173d Airborne Brigade was operating between Ben Cat and Phuoc Vinh. Elements of the 25th Infantry Division and 196th Light Infantry Brigade were to move from the areas of Cu Chi, to the south, and Tay Ninh city, some sixty kilometers to the northwest. The 1st Infantry Division elements were to be air transported to complete the seal and invade the area. Numerous small-scale movements under the guise of local operations would position other forces.
From the first planning conference, strict security measures were enforced to prevent disclosure of the operation. The planning group was held to a minimum within II Field Force headquarters and, wherever possible, preparations were made without specifically identifying them with CEDAR FALLS. All commanders were instructed on 19 December 1966 to minimize helicopter operations during January. Even the plan for the unprecedented mass evacuation of civilians from the area was not disclosed before the operation. Planning for the transportation and housing of refugees was coordinated only with Mr. John Vann, director of Region III's Office of Civil Operations. Although supplies were earmarked for shipment to a refugee relocation center at Phu Cuong, no construction or stocking was started until Cedar Falls had commenced. General Seaman personally briefed the commanding general of the South Vietnamese III Corps on D minus 2, 6 January 1967. South Vietnamese troop participation was approved at that time with government forces assigned the missions of supporting American blocking forces, of securing and transporting civilian evacuees, and of supporting security forces in the An Loc and Quan Loi areas. The Vietnamese III Corps commander assisted in maintaining security by restricting dissemination of information on the operation.
CEDAR FALLS was to be conducted in two distinct phases. Phase I, 5-8 January, consisted of positioning units on the flanks of the Iron Triangle-Thanh Dien forest area. D-day was set for 8 January when an air assault on Ben Suc would take place. Ben Suc was to be sealed, searched, and, after evacuation of its inhabitants and their possessions, destroyed. Phase II of the operation was to start on 9 January with an armored force attacking west from the vicinity of Ben Cat to penetrate the Iron Triangle. Simultaneously, air assaults in an arc around the Thanh Dien forest from Ben Cat to Ben Suc would complete the northern portion of the encirclement of the triangle. Forces would attack south through the entire objective area to the confluence of the Saigon and Thi Tinh Rivers. All civilians were to be evacuated from the area which would be cleared and the tunnels destroyed. Phase II of Operation CEDAR FALLS was planned to last from two to three weeks.
The task organization under II Field Force consisted of three divisions: the 25th Infantry Division under the command of Major General Frederick C. Weyand; the 1st Infantry Division commanded by Major General William E. DePuy; and the South Vietnamese 5th Infantry Division, Brigadier General Phan Quoc Thuan commanding. Forces supporting the operation were the 7th Air Force; 1st Logistical Command; 3d Tactical Fighter Wing; II Field Force, Vietnam, Artillery; the 12th Combat Aviation Group; and the 79th Engineer Group. South Vietnamese supporting forces included the 3d Riverine Company (Navy), the 30th River Assault Group (Navy), and three Regional Forces boat companies.
The U.S. 25th Division would form the anvil for CEDAR FALLS using one organic and one attached brigade positioned along the Saigon River on the southwest leg of the Iron Triangle to conduct search and destroy operations and to prevent enemy forces from escaping. Other elements of the 25th were not directly involved in the operation. The U.S. 1st Infantry Division, employing two organic brigades and one attached brigade, had a threefold mission. Before D-day the division would position elements along the Thi Tinh River, conduct search and destroy operations, and assume screening and blocking positions to keep the enemy from escaping to the east. Commencing D-day (8 January), one brigade would seal, search, clear, and destroy the village of Ben Suc. The third task would be to swing the hammer element of this hammer and anvil operation; that is, to attack west and south with one brigade through the triangle and with another through the Thanh Dien forest. One organic brigade of the division would not be employed in CEDAR FALLS.
On 5 January (D-3), the two U.S. divisions began the deception deployment of the elements which were to participate in CEDAR FALLS.
25th Infantry Division
For Operation CEDAR FALLS, the 25th Division employed its 2d Brigade and the 196th Light Infantry Brigade. Elements of the South Vietnamese 7th Regiment, 5th Infantry Division, were also placed under the control of the division.
The area of operations of the 25th extended on a line generally parallel to the Saigon River from the southern portion of the Boi Loi woods southeast to a north south line four kilometers east of Phu Hoa Dong. This area was some twenty five kilometers long and was designated Blocking Position YANKEE. The division's area of operation encompassed former Viet Cong havens in both the Boi Loi and Ho Bo woods and in the Filhol Plantation. The 25th Division was also responsible for traffic control on the Saigon River. At night, ambushes were to be emplaced along the river; by day, patrols would secure the river, thereby releasing the majority of forces for search and destroy operations.
The 196th Light Infantry Brigade, commanded by Brigadier General Richard T. Knowles, was deployed from Tay Ninh to the Ho Bo woods. Under the guise of a continuation of Operation FITCHBURG-an action initiated earlier in the Tay Ninh area-the 196th was to locate and destroy key enemy installations and fortifications, deny the use of the area as a logistical base and headquarters, and establish blocking positions to prevent enemy escape across the Saigon River. The operational area of the 196th comprised the northern portion of the 25th Division zone of responsibility and was fifteen kilometers long, extending parallel to the Saigon River from the Boi Loi woods on the north to the Rach (stream) Son, immediately northwest of the Filhol Plantation. The task organization included two infantry battalions, two mechanized infantry battalions, two cavalry troops, the 175th Engineer Company, and a battalion (+) of artillery.
At 0540 on D minus 3 (5 January 1967) the 196th Brigade began the move to its CEDAR FALLS operational area, using both ground and airlift. Only relatively light enemy contact was made by the 196th during this final phase of FITCHBURG. As planned, the movement placed the brigade forces in initial positions from which the northern portion of the 25th Division's area of operation could be controlled. Half of the anvil was now in place.
As the 196th maneuvered into position, the 2d Brigade, 25th Division, commanded by Colonel Marvin D. "Red" Fuller, was preparing to be committed. The brigade task organization included two infantry battalions, one tank battalion, two artillery battalions (one each in direct and general support), and an engineer company. Other brigade units included one troop of cavalry (attached on D-day) and a military intelligence detachment.
The 2d Brigade area of responsibility was parallel to and west of the Saigon River from a north-south line four kilometers east of Phu Hoa Dong to the northern perimeter of the Filhol Plantation. The brigade's mission was to block along the Saigon River "early on D plus 1" (9 January) and prevent enemy escape from the Iron Triangle area. Other tasks included maintaining control over the river, preventing its use by enemy forces, and destroying enemy forces and installations in the area of operation, to include the elimination of the hostile infrastructure in the village of Phu Hoa Dong. This last requirement was to be accomplished in conjunction with a South Vietnamese battalion as a "Buddy" operation and was designed to expand government control over the village. Phu Hoa Dong, a complex of hamlets including Ben Co, Phu Loi, and Phu Thuan, located to the west of the Filhol Plantation, was a known enemy communications and liaison point. It was from Phu Hoa Dong that commercial products and taxes could be procured by the Viet Cong 2d Battalion, 165th Regiment, a unit which occupied areas to the east of the town.
Movement by the 2d Brigade into the blocking positions to complete the anvil would begin at 0400 on D-day.
1st Infantry Division
The 1st Infantry Division was to be employed both to block on the east and to conduct extensive search and destroy, tunnel and base camp destruction, and jungle clearing operations throughout the area. In addition, 1st Division forces would constitute the hammer of the operation. Like the 25th, the 1st Division initiated preparatory action for CEDAR FALLS on 5 January, D minus 3, in a cover operation dubbed NIAGARA FALLS. Major forces included the division's 2d and 3d Brigades plus the 173d Airborne Brigade and the 11th Armored Cavalry Regiment (minus one squadron) placed under operational control of the division. For this operation the 173d was code named Task Force DEANE, for its commander, Brigadier General John R. Deane, Jr.
NIAGARA FALLS was a three day operation assigned to Task Force DEANE; it began at 0730 on 5 January. Similar to Operation FITCHBURG conducted by the 196th Light Infantry Brigade, NIAGARA FALLS was a deception designed to place combat elements in position before striking the main blow. The area of operation included the terrain between the Thi Tinh River and Highway 13, bounded on the north by the Cau Dinh jungle and extending south approximately four kilometers. This terrain lies immediately east of the southern point of the Iron Triangle. It was believed that the 2d and 3d Battalions of the 165th Viet Cong Main Force Regiment, the Phu Loi Battalion, and a Viet Cong company (the 63d) might be operating in the area.
NIAGARA FALLS terminated at 1500 on 7 January without major incident. As with the 25th Division units, a deceptive move had resulted in tactical units being positioned, in this case, in Blocking Position ZULU. Enemy escape routes to the east were now closed. Elements of Task Force DEANE would form part of the hammer forces swinging west through the triangle on D plus 1.
Among the accomplishments of NIAGARA FALLS, perhaps the most noteworthy was that of the 1st Engineers. Working with a task force of fifty bulldozers, Lieutenant Colonel Joseph M. Kiernan, Jr.'s troops cleared 365 acres of dense jungle containing many Viet Cong installations and serving as an access route to the Iron Triangle.
The 2d Brigade of the 1st Infantry Division was to seal and search the village of Ben Suc, prepare to evacuate the inhabitants and their possessions, and eliminate the village as a center of Viet Cong operations. The tactical command post along with one infantry battalion left Di An early on 7 January for a road march to the airfield at Bien Hoa. From there the units were airlifted to Dau Tieng. Also on the 7th, the 1st Battalion, 26th Infantry, the unit designated to make the actual assault on Ben Suc, was air transported from Phuoc Vinh to Dau Tieng and came under the operational control of the 2d Brigade. As D-day approached, elements of the 2d Brigade waited in readiness, and the tension mounted.
The third major element of the 1st Division, the 3d Brigade, was slated for search and destroy operations around and through the Thanh Dien forest as a part of the hammer. The operations order was issued to participating battalions of the brigade on 5 January, and the subsequent days were used for planning and preparation. On 8 January the brigade's direct support battalion moved from Lai Khe to Artillery Base I, two kilometers from Ben Cat at the northeast corner of the Iron Triangle. The 3d Brigade was almost ready for its H-hour on D plus 1- 0800, 9 January 1967.
The "Blue Spaders" of the 1st Battalion, 26th Infantry, were set for their raid on Ben Suc; the anvil was ready for emplacement and the hammer was poised. CEDAR FALLS time had arrived.
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As dawn broke on D plus 1 (9 January 1967) the units forming the anvil of Cedar Falls were maneuvering into their final positions as the 1st Division's 2d Brigade continued its day-old operation in Ben Suc. The hammer forces of the 1st Infantry Division (the organic 3d Brigade and Task Force Deane) initiated their assault at 0800 with simultaneous attacks across the Iron Triangle and into the Thanh Dien forest. The impact of the hammer on enemy forces was imminent.
3d Brigade
The mission of the Iron Brigade was to conduct airmobile assaults with five battalions into the Thanh Dien forest, conduct search and destroy operations to kill or capture enemy forces, destroy enemy installations, and evacuate all inhabitants from the area of operations. The operations order had been issued to all participating battalions on 5 January, and the previous four days had been spent in detailed planning and preparation. The initial positions for the elements of the 3d Brigade formed a semicircle to the north of the Thanh Dien forest. Six landing zones (LZ's) were designated. The terrain in this area ranges from flat to gently rolling; the undergrowth is dense. The few streams in the area are fordable with minor difficulty.
The 3d Brigade's area of operation, according to intelligence sources, was thought to be an important supply base and hospital area. The enemy units believed to be in the area were listed as base caretaker elements and headquarters defense units. The Americans expected to find base camps and supply installations and well-constructed bunkers, tunnels, and trenches, all protected by extensive mines and booby traps. These expectations proved to be accurate.
Major units constituting the task organization of the 3d Brigade included five infantry battalions, two cavalry squadrons, and one artillery battalion. At 0735, 9 January, an extensive air and artillery preparation began on Landing Zone 1, the northernmost point of the ring of men and weapons that was soon to be formed around the Thanh Dien forest. For the 3d Brigade and the 1st Battalion, 2d Infantry, commanded by Lieutenant Colonel William C. Simpson, Operation CEDAR FALLS began at 0800 as the first of sixty helicopters touched down. The entire battalion was on the ground in less than five minutes. The artillery and air strikes turned three kilometers toward the east and Landing Zone 2. At 0840 Lieutenant Colonel Rufus C. Lazzell and the 1st Battalion, 16th Infantry, joined the battle. At 0910 the first enemy reaction to this portion of the operation occurred in the vincinity of Landing Zone 1 in the form of small arms fire. There were no casualties. By this time the preparatory fires had shifted to the west and Landing Zone 3.
The 2d Battalion, 28th Infantry, under the command of Lieutenant Colonel Elmer D. Pendleton, started landing at LZ 3 at 0920. As the battalion expanded its zone of operations, the first indications that the enemy was retreating were noted. Within twenty minutes the infantrymen had found several freshly dug foxholes, recent oxcart tracks, a tunnel containing a pot of steaming rice, and a cache of munitions. located next was a 55-gallon drum of diesel fuel, a 66-pound enemy mine, and a newly constructed base camp. Two light observation helicopters overflying the area of operation were hit by ground fire and so damaged that they had to be evacuated. Small quantities of weapons and munitions continued to be found.
At 1155 the 1st Battalion, 28th Infantry, commanded by Lieutenant Colonel Jack G. Whitted, touched down on Landing Zone 5, located between Landing Zones 1 and 3, and began search and destroy operations.
By noon the 2d Battalion, 28th Infantry, was reporting sniper fire and seeing an unknown number of Viet Cong escaping to the south on bicycles. Near Landing Zone 3 the battalion found an arms cache in an enemy base camp which included 2 recoilless rifles, 1 60-mm. mortar, and 135 Russian rifles. In the same area they soon uncovered some grenades, 24 gas masks, 75 tons of rice, and 4.5 tons of salt.
By midafternoon the 3d Brigade set up a forward command post for communications at the now secured village of Ben Suc. The battalions of the brigade now in the operational area continued their search and were uncovering large quantities of materiel and abandoned enemy installations.
At 1350 the 2d Battalion, 18th Infantry (less Company A), passed to the operational control of the 3d Brigade and prepared to air assault into the operational area. At 1600, as the first lift of the battalion under the command of Lieutenant Colonel Lewis R. Baumann was going into a landing zone three kilometers south of LZ 3, two claymore mines were detonated by the enemy. An alter-nate landing site was designated three kilometers to the west where the battalion landed without incident. The battalion then reverted to the operational control of the 2d Brigade.
At 1820 the 2d Battalion, 28th Infantry, apprehended sixty per-sons four kilometers north of Landing Zone 3. They were moved to the evacuee holding area at Ben Suc.
As darkness fell, night defensive positions were established by these five combat battalions now in the Thanh Dien forest sanctuary of the Viet Cong.
Task Force Deane
At 0800 on 9 January the 11th Armored Cavalry Regiment attacked west from its staging areas near Ben Cat. After securing the bridge across the Thi Tinh River and Position GREEN, one kilometer to the southwest, the regiment knifed toward its objec-tives some seven kilometers to the west. By 1000 the Blackhorse
Regiment had penetrated the entire width of the Iron Triangle from east to west and had severed it from the Thanh Dien forest on the north. Only slight enemy resistance had been encountered.
The 2d Battalion, 503d Infantry, commanded by Lieutenant Colonel Robert H. Sigholtz, air assaulted at 1115 into Landing Zone 4 on the northeast perimeter of the semicircle encompassing the Thanh Dien forest. By 1145 the battalion had linked up with the infantrymen of the 1st Division who had landed earlier.
Landing Zone 6, the eastern anchor of the tightening ring around the forest, was the next to be occupied by 1st Division forces. At ~1235 the 4th Battalion of the 503d Infantry (-), commanded by Lieutenant Colonel Michael D. Healy, air assaulted into Landing Zone 6 and seventy minutes later had joined forces with the 2d Battalion. Blocking positions were established and limited search and destroy operations conducted. These two battalions of the 503d brought the total number in and around the Thanh Dien forest to seven.
Meanwhile, to the south, the 1st Battalion, 503d Infantry (Lieutenant Colonel Robert W. Brownlee), and 35th Ranger Battalion (with elements of the 1st Squadron, 4th Cavalry) maintained the blocking positions opposite the southeast side of the triangle held since the termination of NIAGRA FALLS.
25th Infantry Division
On D plus 1 the anvil forces of the 25th Infantry Division assumed, prepared, and improved their final blocking positions and actively conducted search and destroy operations along the west bank of the Saigon River. Tankdozers assisted in clearing the areas.
Units of the 2d Brigade continued operations in the southern sector of the division area of responsibility. At 1645 at a point on the Saigon River four kilometers northwest of Phu Hoa Dong, Company B. 2d Battalion, 34th Armor, engaged a raft with fifteen Viet Cong aboard. Employing 90-mm. guns loaded with "cannister and shot," the men of Company B destroyed the raft and killed all occupants. The brigade continued to find quantities of munitions, weapons, and rice in the numerous huts, tunnels, and bunkers, many of which were mined and booby trapped. Three sampans were located and destroyed.
The 196th Light Infantry Brigade continued its mission in the northern area of the division sector. The hamlet of A Go Noi (1) was searched and the inhabitants screened; a medical team, part of the search and destroy forces, treated the inhabitants. Nine Viet Cong were shot as they tried to cross the river during the hours of darkness. Several classified papers were captured during the day, documents which pertained to the postal, communications, and transportation section of Military Region IV. One paper classified top secret concerned economy of ammunition by Viet Cong units. It stated that ammunition could no longer be provided for Ameri-can weapons and that in the future money would be furnished for the purchase of such ammunition. It went on to say that ammuni-tion for Chinese weapons would be limited. The paper included a price list for weapons and ammunition that the Viet Cong should use when making purchases.
Small Unit Actions
Operation Cedar Falls was characterized by small unit actions. Typical are those of Company C, 2d Battalion, 503d Infantry, on 9 January as reported in the 173d Brigade's after action report. On the morning of 9 January Company C was located in Position BLUE, ten kilometers east of the Iron Triangle. At 1055 the company was airlifted out of its pickup zone and twenty minutes later landed in LZ 4 on the northeast corner of the perimeter sur-rounding the Thanh Dien forest. Its mission was patrolling, form-ing blocking positions, and setting up night ambushes.
Each rifleman of the company was armed with an M16 rifle, 400 rounds of ammunition, 2 smoke grenades, and 2 fragmentary grenades. There were 2 M60 machine guns in each of the three pla-toons; each gunner carried a total of 1,500 rounds of ammunition. In addition, each squad had 2 M79's (grenade launchers) with 45 rounds per grenadier and an average of 2 claymore mines. The company as a whole was equipped with 3 81-mm. mortars with 30 rounds per mortar. Each individual carried 3 C-ration meals while on operations.
By 1130 on 9 January the company had cleared its landing zone and was establishing a blocking position. Captain Thomas P. Carney, the company commander, moved to the right flank to coordinate with the commander of the unit to the north - Company B. 1st Battalion, 16th Infantry. With the coordination completed, the company's three platoons established defensive positions along an oxcart trail west of the Thi Tinh River. The company's area of operation was primarily dense jungle with the exception of one section which had been defoliated within the last year. Based upon an assessment of the situation and terrain by the two adjacent company commanders, night ambush patrols were to be placed on an overgrown trail in the western portion of the perimeter. After the defensive position had been established, patrols were sent out to search the immediate area for signs of the enemy and for possible ambush sites. The 3d Platoon soon discovered a hut connected to a combination tunnel and bomb shelter. That the hut had been inhabited recently was confirmed by the freshly cooked rice which was found. Further search of the area revealed a cache of twelve bicycles and 200 pounds of polished rice on a concrete platform. Everything was destroyed with the exception of the bicycles, which were later to provide transportation for the men of "Charlie" Company while in base camp. The 33-man weapons platoon found one small hut while screen-ing to the rear of the company command post. After destroying the hut, the platoon moved east toward the Thi Tinh River and found a fordable stream. The platoon then returned to the company base area. Sergeant Nathaniel King was in charge of the 1st Platoon's patrol. Two foxholes were discovered; neither showed signs of recent use. Sergeant King also reported finding a footpath running parallel to the overgrown trail in the western portion of the company's position. Although the trail showed no signs of recent use, there was evidence that the small footpath was heavily traveled, probably because it could not be observed from the air.
All patrols returned to the command post by 1630. Hot A rations and a .50-caliber machine gun arrived by resupply choppers, and the company settled down to warm chow.
During darkness the company employed three-man listening posts around its position. One post located between the 2d and 3d Platoon positions was occupied by Sergeant Frank Bothwell, Specialist Four Walter Johnson, and Private First Class Joseph Russo. They had moved into position shortly after nightfall, situating themselves three meters from one another in a triangular position for easy communication and 360-degree observation. The terrain was generally flat and overgrown with elephant grass and bamboo. The men were instructed not to engage the enemy unless absolutely necessary.
The three men lay quietly. After minutes of silence, movement was detected at about 1940 at a distance of approximately fifty meters. The noise became louder. Because of the thick vegetation, vision was limited. The men were prone and could not move without being detected. The enemy was now nearly on top of the position. Sergeant Bothwell knew that if he reached for his M16, the noise would be heard; he prepared to throw a fragmentation grenade instead.
Johnson was in a better position to observe the enemy; however, he knew he must come to a sitting position to fire and would thereby expose himself and his comrades. However, as the enemy came closer, Johnson realized that the time for action had come. He sprang to a sitting position and fired approximately five rounds before his weapon jammed. An enemy grenade exploded and a fragment hit Johnson in the neck. In an attempt to have his grenade detonate on impact, Bothwell had pulled the pin, released the handle, paused three seconds, then tossed it toward the enemy. The grenade, however, exploded in flight and rained fragments on the position. Russo was wounded in the hand and was unable to fire his M79. Bothwell radioed back to the command post informing them of the casualties; he then sprayed the area with M16 fire and, assisting Johnson and Russo, withdrew to the company position.
The wound in Johnson's neck, although not fatal, was very close to the jugular vein. The medical evacuation helicopter arrived twenty-five minutes later and evacuated the two men.
While the listening post was seeing action, an ambush patrol under Sergeant Julius Brown had been in position near the footpath. The patrol had left the command post at 1900 and moved south along the path, passing its ambush site and then backtracking to it to mislead any enemy elements following them. The ambush site had been chosen because of the cover available and the indications that the path was frequently traveled at this point. There were nine men in the patrol, six armed with M16's, two with M79's, and one with an M60 machine gun. The patrol maintained radio silence but was able to receive any messages transmitted to it. Captain Carney received reports from adjacent units that movement had been detected near their company command posts. He warned Sergeant Brown to keep on the alert for infiltrating Viet Cong.
At 1945 came the sounds of firing from Sergeant Bothwell's listening post. Shortly thereafter another warning of enemy activity in the area was received. The ambush patrol lay quietly waiting.
At 2045, sounds of movement were heard near the ambush site. Private First Class Gary Gaura became anxious and crawled to Sergeant Brown's position a few meters away to get instructions. Brown told him to do nothing and be still. When Gaura crawled back to his position, he coughed, and the enemy, now only about fifteen meters away, halted sharply. The Viet Cong remained silent and motionless for approximately ten minutes and then moved on around the patrol's killing zone. Private Gaura counted fifteen silhouettes. The enemy crossed the trail, avoiding the ambush, yet remained in the immediate area.
About one and a half hours later, the enemy column moved to the west and out of range and sight. Fifteen minutes later machine gun fire was heard from the direction of the adjacent company. At 2300 the sound of movement was again heard and out of the brush came a single enemy soldier. He cautiously moved toward the ambush position. Again someone coughed, alerting the enemy, but this time it was too late; there was no chance for escape. Private First Class Michael Farmer, armed with the M60 machine gun, squeezed off five rounds. The enemy fell wounded. Another enemy soldier emerged into the ambush site. He looked at the wounded man, turned, and walked away. The wounded man cried out. The straggler wheeled, sprayed the area with automatic weapons fire, and proceeded toward the man on the ground, walking so close to the ambush position that he nearly tripped over the barrel of the M60. Bending over, he lit a candle which illuminated both men. Private First Class Michael Hill fired his M60 machine gun but it malfunctioned; simultaneously Private First Class Martin Norman fired his M16. The candle went out. Silence was maintained until morning when the two enemy dead were found along with two AK47 weapons. Among their personal items was a document containing codes for the Military Region IV headquarters; it appeared that the second Viet Cong had been a courier whose job was to transport important documents.
At 0630 the ambush patrol moved out of the area and returned to the company command post.
It later developed that the captured documents were one of the most significant finds of the operation and had a direct bearing on the subsequent capture of a high official assigned to Military Region IV.
Action proceeded in the Iron Triangle and Thanh Dien forest as the hammer continued its swing toward the anvil. On the morning of 11 January, General Seaman sent a message to the commanding generals of the 1st and 25th Divisions. After congratulating them on achieving initial surprise and on the encouraging results of the operation, he concluded by saying ". . . I want a thorough search to be made of the area of responsibility. . . . I particularly desire that the Iron Triangle be completely covered." It was in the spirit of this message that Operation CEDAR FALLS was conducted until its termination sixteen days later.
The operation was characterized by numerous small unit actions with both the hammer and anvil forces continuing to uncover increasingly large amounts of supplies. The men of the 1st and 25th Divisions searched meticulously, stripping the Iron Triangle and the surrounding area of all they could find that might be of value to the enemy. The enemy's defenses were weak and disorganized and had evidently been shattered by the mass and surprise of the attack. Mines, booby traps, and snipers were encountered, but there were no organized defenses or counterattacks. The enemy had evidently ordered units to disperse and try to escape. Because of the tight seal around the triangle, this was not always easy.
25th Infantry Division
Forces of the 25th Infantry Division continued search and destroy and search and clear operations along the Saigon River. The action was typified by company-size sweeps of assigned areas of operations. An entry in the 2d Brigade's after action report summarizes the activities of the 1st Battalion, 27th Infantry, on 17 January, which were fairly illustrative of the activities of the other units:
CO. A 1/27 conducted S&D [search and destroy] operations between AP NHA VIEC and the Saigon River. B 1/27 continued road clearing operations in sector. C 1/27 continued to outpost Saigon River. At 0947 hours A 1/27 destroyed one sampan, one bunker. At 1223 hours C 1/27 located 600 pounds rice. At 1350 hours C 1/27 destroyed four bunkers, and
located miscellaneous documents. At 1515 hours A 1/27 destroyed three CBU's. At 1517 hours C 1/27 destroyed two bunkers. At 1531 hours A 1/27 located one VC KIA. At 1615 hours C 1/27 destroyed seven bunkers, six huts. At 1622 hours A 1/27 destroyed two bunkers. At 1720 hours A 1/27 destroyed two bunkers, one building, 200 pounds salt. At 2200 hours C 1/27 destroyed two sampans, two VC KIA (POSS).
The locations cited for these entries were all within one kilometer of the Saigon River in the vicinity of its junction with the Thi Tinh River.
The brigade elements also continued to work closely with the South Vietnamese 2d Battalion, 7th Regiment, in and around the village of Phu Hoa Dong.
Elements of the 25th Division continued to search the enemy base areas in the Ho Bo woods and Filhol Plantation while blocking enemy escape routes out of the Iron Triangle. Although most enemy contacts were with small scattered groups attempting to escape, one company did engage an enemy platoon and another destroyed a sampan with thirteen Viet Cong aboard: Buddy operations employing U.S. troops and the Vietnamese 5th River Assault Group patrolled both banks of the Saigon River to help seal off the triangle.
In accomplishing its objective of denying the enemy access to the Saigon River, the 25th Division employed various tactics, as described in a news release from the 25th Division's public information office:
CU CHI, VIETNAM (IO)-Part of the 25th Infantry Division's mission in Operation "Cedar Falls" was to seal off a portion of the Saigon River to all traffic. The Saigon River is a favorite escape route of the Viet Cong and the banks of the river are dotted with heavily fortified weapons emplacements.
"Tropic Lightning" soldiers used aerial observers and gunners and a waterborne force of RAG (River Assault Group) boats manned by infantry-men armed with automatic weapons and rifles. The RAG boats patrolled the river around the clock, raking the banks with their heavy firepower, while the gunships of the Division's D Troop, 3rd Squadron, 4th Cavalry, peppered fortifications and sampans alike with aerial rockets and machine gun fire.
As the operation continued, the Viet Cong began to realize that the airborne-waterborne, one-two punch made the Saigon River a boundary they could not afford to come near, let alone cross. Even at night the river was sealed. The RAG boats used searchlights to probe the darkened shoreline, and tanks used their high intensity Xenon lights to scan the water and the aviation units used the firefly team with a 1,750,000 candlepower beam to scan both areas. With these tools, very little escaped their surveillance.
Despite the destruction and sporadic contact which were occurring, the division forces found the time and occasion for civic
action activities, as noted in the following extracts from the after action report of the 2d Brigade, 25th Infantry Division:
11 Jan 1967 . . . 2d Bn, 27th Infantry
A MEDCAP [Medical Civic Action Program] was conducted on the out-skirts of forward base camp and 38 patients were treated. This number is not impressive except that the people in this area had been indoctrinated by the VC that American medicine would harm them. One woman had an ill child but would not let the doctor give it medicine. Several days later this woman returned and allowed the child to be given medicine since she had seen that the medicine did not harm others who had taken it. On 11 Jan the MEDCAP also distributed candy and toys to the children.
15 Jan 1967 . . . 2d Bn, 27th Infantry
Civic Action: MEDCAP operations were again conducted at base camp, where 163 patients were treated. This, it should be noted, was a tremen-dous increase over the first day's total of 38 patients, and indicates the continued progress in gaining the respect of the local civilians.
To the north of the 25th Division's 2d Brigade, the 196th Light Infantry Brigade was conducting similar operations in its area of responsibility. Using patrols, company-size search and destroy
operations, and periodic platoon airmobile assaults, the brigade uncovered numerous installations containing caches of enemy munitions, food, clothing, documents, and equipment. One company reported during this time that it had "engaged 14 bushes floating upstream resulting in 10 VC KIA (Possible)."
Another low-key report was submitted on 18 January by the 1st Battalion, 5th Infantry, and stated simply: "At 1730 hours Company A discovered an extensive tunnel complex." However, it developed that this discovery probably uncovered the headquarters of Military Region IV or at least a significant portion of it.
The tunnel system was located adjacent to the stream (the Rach Son) which marked the 196th Light Infantry's south boundary, on a narrow strip of relatively clear land between the Ho Bo woods and the Filhol Plantation. In the first few hours after its discovery, the vast complex yielded forty pounds of documents including detailed maps of Saigon and the Tan Son Nhut area, maps showing the schemes of maneuver of friendly operations in the area and Viet Cong routes of movement from the Iron Triangle area to the Saigon River.
Newsweek magazine described the tunnel discovery in these words:
Entering the shaft head first through a small hole that descended to the tunnel floor some 16 feet below, the tunnel rats spread out through the winding galleries. Soon they realized they were on to something big. In their haste to escape, the Viet Cong had left behind not only medical supplies and weapons but maps, diagrams of U.S. billets in Saigon and other plans for terrorists raids. One of the documents outlined the plan for the December 4 raid on Tan Son Nhut air base. Brigadier General Richard Knowles, commander of the 196th, was clearly convinced that his men had found the headquarters for all Viet Cong activity in the Saigon region. "This is by far the most important one yet," said Knowles last week. "This was his headquarters."
Company A, together with other elements of the battalion, searched the tunnels during the next six days. Time magazine related the story of the complex's end:
There were a few Viet Cong defenders left behind, and the G.I.s, equipped with silencer-mounted .38 pistols, pursued them through the labyrinth. After exploring the maze for 1,000 yards, the tunnel rats came up and turned the task over to units that pumped riot control agents through the system, then set about blasting it to dust.
Small villages in the area were searched and cleared. Armed helicopters, used deceptively, orbited the villages before the ground forces moved in, as described by General Knowles:
Armed helicopters proved to be extremely valuable in search and clear operations of villages. It was observed on Cedar Falls that armed helicopters on station would prevent the VC from fleeing the village into the rice paddies. Once armed helicopters would leave the area, it was discovered the VC would try to make their escape from the village being searched. One technique which proved successful was to have the armed helicopters leave the village area for four to five minutes. The VC, think-ing the helicopters had left for good, would then try to make their escape. The helicopters would then return and observe the VC fleeing and take them under fire.
The 196th Light Infantry Brigade terminated Operation Cedar Falls on 25 January when the last elements left the operational area and closed at their Tay Ninh base camp. The organic battalion of the 25th Division which had been attached to the 196th was released and moved overland to Cu Chi, the base camp of the 25th Division. However, the 25th Division's operations had proved so profitable that elements of the 2d Brigade continued to search the area as part of Operation ALA MOANA after the termination of CEDAR Fares on 26 January.
1st Infantry Division
On 10 January two South Vietnamese battalions relieved the 1st Squadron, 4th Cavalry, of its security mission along the Thi Tinh River, and the squadron came under the operational control of the 11th Armored Cavalry Regiment (and Task Force Deane) and took over the blocking assignments of the 2d and 4th Battalions, 503d Infantry, along the east side of the Thanh Dien forest perimeter. The following day these two battalions, under the control of Task Force DEANE turned southward.
Having been relieved of the Ben Suc seal mission by the two South Vietnamese airborne battalions on 10 January, the 1st Battalion,26th Infantry, still under the 2d Brigade, was committed on the next day to assisting in the search of the Thanh Dien forest.
1st Division forces combed the enemy sanctuary throughout the remaining days of the operation and found huge quantities of rice, hundreds of documents, and many enemy weapons and much ammunition; destroyed enemy tunnels and bunkers; and stripped trees and underbrush from roads and trails and carved out landing zones for future operations. By 12 January 1st Division forces had captured 1,800 tons of rice, 189 small arms, and 971 grenades. The 1st Battalion, 2d Infantry, had located a 100-bed underground hospital complete with blankets and equipment along the north-western edge of the Thanh Dien forest.
The two battalions of the 503d Infantry attacked south into the triangle, with units of the 11th Armored Cavalry Regiment screening on the north and augmenting the infantry battalions in search
During Operation CEDAR�FALLS it was observed that anytime a large cache of rice had been discovered a flock of small birds had been frightened away by the approach of friendly troops. Accordingly, any time a flock of birds was noticed, a search for a rice cache was made in the area.
Only light and occasional contact continued with the enemy while the task force moved south uncovering quantities of material and numerous fortifications.
As the operation continued, the number of enemy Chieu Hoi (open arms) ralliers grew well beyond previous totals. Psychological Operations field teams effectively exploited these ralliers by printing rapid reaction leaflets containing surrender appeals from the ralliers to their Viet Cong friends. Typical of the messages dropped was one written by rallier Le Van Sa. Printed on both sides of 5x8 inch paper, 50,000 copies were disseminated in the 1st Infantry Division's area of operations: To my dear friends still in the VC Ranks, I am Le Van Sa, medic of the medical team of VH (MB 3011). I followed the VC by their false inducement. I found fault with our people and nation. I have gone the wrong way. But in time I found out what is right and what is wrong. I have rallied to the GVN and have been warmly welcomed, well treated. At the present time I am very happy at the CH (Chieu Hoi) Center. I also saw my family who are living in the Resettlement Center of GVN. I send to you this letter so that you too could rally to the Government side where you can start a new life and see your families. My dear friends: Hung, Rong, Tieng, Chi, Tu Dan, Minh Nhan, Tha Luong, Tam Thu. Thanh, Huyen, Lion, Thau, Mong Tieng, Ut and Gan, all of you should return to GVN as soon as possible. Staying with VC, you will have no place to hide. You can use any Chieu Hoi leaflet and take the nearest road to report to the Government or Allied Military Installations. You will be treated as we are now. There are more than 300 VC who have returned to the National Just Cause in a very short time. They are having a good living here at the CH Center. They have been well treated. My dear friends you should rally right now to avoid useless deaths. Tet is going to come very soon. Rally to reunite with your families. The door of the Chieu Hoi Center is wide open for your return. The leaflet also bore a photograph of Sa.
In addition to these quick reaction messages directed at individual Viet Cong by name, more general messages were also dropped encouraging the Viet Cong to give up. One such message read:
To VC of South Ben Cat, the powerful GVN and Allied Forces will continue extensive operations in the area of Ben Suc and south Ben Cat. All base camps will be destroyed and the area will be subjected to continuous artillery fire and air strikes. Huge areas of jungle are being removed and there will be no safety for VC anywhere. You will no longer find shelter or supplies here, and you will not have safe base camps. All VC remaining in this area will meet inevitable death.
From 8 to 15 Jan 67, 259 of your comrades have been killed and 60 captured, and numerous other supplies, clothing and equipment have been captured or destroyed.
More than 200 of your comrades have already rallied to the GVN and are receiving good treatment. Rally now and start a new life of happiness, united with your families. Turn yourself in to the nearest government office. A government office is located in Ben Cat where you will be welcomed with open arms and given protection. Walk to any road that leads to Ben Cat - stay on the road - walk at all times - if you run your intentions may be mistaken and you may be killed. Use the sketch map on the back of this leaflet as your guide to safety and freedom. Rally now before it is too late!
On the reverse side of the 5x8 inch sheet was a map of the Iron Triangle.
Over five hundred Viet Cong surrendered during the operation, many as a result of the Psychological Operations but most because the continued presence of allied troops gave them no choice when they became hungry, wet, and out of supplies and support.
The evacuation of civilians from Ben Suc and the other three villages in the triangle continued through 16 January. About half of the inhabitants made the journey to the Phu Cuong resettlement camp in Chinook helicopters or South Vietnamese Navy craft down the Saigon River. After the road from Ben Cat to Ben Suc via Rach Bap was passable, the other 3,000 traveled by truck convoy. This unprecedented mass evaucation, executed on short notice, required a tremendous effort by U.S. and South Vietnamese military and civilian agencies; but it would be weeks before the latter could restore a sense of normality to the evacuees. Eventually they would have their own village with its school, raise their own crops with access to the Saigon markets, and have much-needed medical assistance available. Meanwhile, a source of supply and support for the Viet Cong had been eliminated.
By 14 January the forces of the 1st Division were starting grad-ually to wind down CEDAR FALLS. However, before they did, the Blue Spaders of the 1st Battalion, 26th Infantry, moving to the northwest of Ben Suc, uncovered one of the more highly developed and strongly built enemy complexes to be found in the area located less than one kilometer from the Saigon River. This is the descrip-tion of it contained in the after action report of the Big Red One's 2d Brigade:
Building #1 was approximately 9 feet wide by 18 feet long and 10 feet below the surface of the ground. The building had cement on all four sides and flooring about 5 inches thick. The only overhead protection was afforded by sheets of tin. On the northwest corner was a bunker with no overhead protection. Beds and tables were on the floor.
Build #2 was approximately 9 feet wide by 12 feet long and 10 feet below the surface. It had concrete identical to Building #1. Overhead cover over one-half of the structure consisted of 5 inch logs and 3 feet of packed dirt. There were no fighting positions located near the building and beds were located on the 1st floor and on top of the overhead protection. Building #3 and #4 were exactly identical to building #2.
Bunker #5 located north of the camp and connected by tunnel to building #3 had overhead protection of 5 inch logs and 3 feet of packed dirt. There were four firing apertures, each 2 inches high and 4-6 inches wide and each could cover an area over 100m wide to the front.
The second level tunnel going north was made so that at every 10-15m it came to a dead end; and a trap door on the floor connected with a tunnel which went down, around and back up to the other side and on the same level with the fake dead end. There were two small holes in the dead end permitting one man to observe and fire through the tunnel.
On 17 January the 2d Brigade ended its participation in CEDAR FALLS. By 18 January the 3d Brigade had withdrawn. Task Force DEANE terminated CEDAR FALLS on 25 January while the 1st Squad-ron, 4th Cavalry, continued road security in the triangle for the departing engineer work parties. At midnight, 26 January 1967, the operation came to a close.
Starting with the construction of the D. S. [double-single] Bailey Bridge at Ben Cat on 21 Dec 66, and ending with the demolition of the tunnel complexes on 26 Jan 67, Operation Cedar Falls was without exception the most significant combat engineering operation of the war to date. New concepts of jungle warfare using dozers to open heretofore inviolable VC strongholds; the emergence of a new "Secret Weapon," the dozer infantry teams; and combined acetylene and HE (High Explosive) tunnel demolitions; all have proven unique, successful, and of tremendous value to future operations. Operations Niagara Falls and Cedar Falls introduced massive jungle clearing in conjunction with tactical infantry operation on a scale never attempted before. A total of 54 bulldozers were under the OPCON (Operation Control) of the 1st Engineer Battalion. . . .
So spoke Lieutenant Colonel Joseph M. Kiernan, Jr., commanding officer of the 1st Engineer Battalion, in summarizing engineer operations during CEDAR FALLS.
Engineer and chemical operations during CEDAR FALLS involved innovative techniques as well as others more familiar and routine. Engineer forces were assigned normal missions such as the construction of a Bigfoot Bailey bridge before the operation to facilitate the movement of the 11th Armored Cavalry Regiment into the Iron Triangle and the clearing and construction of landing zones, roads, and support areas. More unusual projects included the clearing and destruction of enemy underground complexes during search and destroy operations, the stripping of acres of jungle, and the establishment of a waterborne seal at the confluence of the Saigon and Thi Tinh Rivers to prevent enemy escape. The dropping of CS munitions from helicopters and the destruction of rice were entrusted to the chemical personnel.
The engineer-chemical task force for CEDAR FALLS had under Colonel Kiernan's command some six hundred men from the 1st Engineer Battalion, flame-thrower platoons from the 1st Squadron, 4th Cavalry, the "tunnel rats" (tunnel exploration and demolition crews) from the 242d Chemical Detachment, and approximately three hundred engineers from the 79th Engineer Group. This last complement consisted of men and equipment drawn from four engineer battalions, a light equipment company, and a maintenance detachment.
Bridge on the Thi Tinh
To provide rapid crossing for the 11th Armored Cavalry Regiment and supporting forces as they launched their sweep from Ben Cat toward objectives on the opposite side of the Iron Triangle, the 1st Engineer Battalion of the Big Red One was directed to construct a Bailey bridge over the Thi Tinh River just west of Ben Cat. Work commenced on 21 December, well before D-day, at a site adjacent to an existing Eiffel bridge and a destroyed concrete bridge. The bridge site preparation included the destruction of the remains of the concrete bridge, the construction of headwalls on each bank, and the construction of an eight-pile pier in the center of the river to support the Bigfoot Bailey bridge sections. The assembly of the bridge was begun on 31 December, the launch made on 1 January, and the final welding done by 5 January.
Disaster struck the new bridge on the afternoon of 9 January when a recovery vehicle towing a disabled M-48 tank crashed through the western span. All traffic was halted and an emergency repair crew of the battalion was directed to remove both vehicles from the river and replace the damaged span temporarily with an AVLB (armored vehicle launched bridge). The Eiffel bridge, which had also been damaged by the collapse of the Bailey, was reinforced and opened by 1630, although limited to medium truck traffic. To launch the AVLB, the Bailey span had to be removed from the pier and disassembled- a difficult and time-consuming task. The western approach was extended twenty feet by earth fill and was bolstered by damaged Bailey parts. The shorter (hotfoot) AVLB was successfully launched by 0515 the next morning. The bridge was opened to traffic at daybreak.
Jungle Clearing Operations
During late December 1966 and early January 1967, the engineer task force structure and support role in preparation for the vast amount of jungle clearing for CEDAR FALLS were developed and partially tested in Operation NIAGARA FALLS. The tractor assets from the engineer battalions of the 79th Engineer Group were consolidated under the headquarters of one of its battalions, the 168th, to support the 1st Infantry Division. Experience in NIAGARA FALLS had revealed that the tractors must have an "in-house" maintenance capability to provide on-spot servicing and small repairs; thus, a composite maintenance task force was organized. There also was an attachment from a maintenance battalion which could fabricate parts. Unit and tractor-type integrity was maintained by dividing the personnel and equipment into teams. The decision was made to employ the dozer-infantry team. Tankdozers, bulldozers, Rome Plows,* and the infantry would cut into the enemy-infested jungle together, simultaneously clearing the area of vegetation, conducting search and destroy operations, and destroying enemy fortifications.
The dozer-infantry teams used two techniques based upon the tactical situation and the basic characteristics of the equipment. One was a formation of two tankdozers at the point, followed by four bulldozers abreast, with two more dozers as a cleanup team to windrow the vegetation that had been cut. Infantry supported the tractors, at the same time carrying out search and destroy missions. The second technique employed a Rome Plow in the lead followed by troops in armored vehicles. When contact with the enemy was made, the men in the vehicles provided fire support until the accompanying infantry could silence the enemy.
A significant advantage of the dozer-infantry team was the additional time it gave the infantry to conduct search and destroy operations. During previous jungle operations the infantry often had been forced to stop to clear resupply landing zones by hand. With the dozers along they could do the clearing, and do it in minutes.
The test of the jungle clearing concepts in NIAGARA FALLS had revealed that the three or four weeks planned for CEDAR FALLS were not adequate to clear the entire jungle in the Iron Triangle. Instead, only 7 or 8 percent of the sixty three square miles of jungle area could be cleared in that time. Therefore, only strategic areas such as those along roads and landing zones would be cleared, plus paced swaths to permit rapid deployment by mechanized and air-mobile units in future operations. The swaths were defined as the operation progressed.
The CEDAR FALLS clearing operations commenced on the afternoon of D plus 1, 9 January, the same day that three engineer base camps were scratched out of the north side of the triangle and spaced along the eight kilometers of road between Ben Cat and Rach Bap. A half mile of clearing along the roadway, fifty meters wide, was also cut that first day. On the following day over 3,300 meters of jungle were torn apart. Also on the second day an engineer platoon with the mission of clearing a landing zone scrambled down the 70-foot ladder from a Chinook hovering over the jungle and joined the 1st Battalion, 28th Infantry, in the Thanh Dien forest. Two hours later the landing zone was ready to receive the first helicopter; later it was enlarged to accommodate four at a time.
In this operation as in most utilizing a large amount of heavy mechanical equipment, the two major problems were fuel resupply and vehicle maintenance. Each dozer team consumed 600 gallons f diesel fuel per day. Usually at least six refueling locations- some supplied solely by 500 gallon pods brought in by air-were required daily. Several teams had to be supplied on site by air. When field pumps were in short supply, trenches eight feet deep were dug and the fuel was gravity-fed from the top of the cut into the vehicles. Maintenance problems were compounded by the quantity of equipment involved and the distances between teams. Repairs were made in the field whenever possible; otherwise the disabled vehicle was moved by truck to Lai Khe where heavy maintenance support was provided by elements of the 79th Engineer Group. The maintenance task force operated around the clock and was the significant factor in achieving the very low deadline rate (percentage of vehicles not usable because of needed maintenance) of 10 to 15 percent for tractors and dozers throughout the operation.
Engineer clearing operations continued until 22 January with some impressive results. The jungle area cleared totaled 2,711 acres or 10.9 square kilometers, including 50 to 100 meters of jungle on each side of the major roads in the Iron Triangle as well as 34 landing zones tactically spaced throughout the triangle. Three of the zones were cleared by engineers lifted into the jungle by helicopter, the remainder by dozer-infantry teams. In addition, numerous swaths were cut through the jungle, usually in widths from 50 to 100 meters. During the clearing, many small engagements occurred between the engineers and enemy snipers, and, in one instance, an enemy squad. Numerous booby traps were also encountered. However, the 1st Engineer Battalion had only 1 man killed and 7 wounded by hostile action during the operation, while the supporting engineer units had 7 wounded.
Tunnel Exploration and Destruction
Enemy combat units generally did not use tunnel systems. Rather, as do most military forces, they relied on fighting positions, trenches, and bunkers for protection. Tunnel systems were dug by those relatively stationary Viet Cong elements such as village and hamlet cadres, logistical units, and headquarters elements. Consequently, tunnels were most often found in the enemy-controlled villages and logistical base areas but not necessarily in combat unit base camps. Interrogated prisoners and returnees revealed that as a rule personnel of organized Viet Cong combat units did not know the location of such tunnels. They might frequently reveal the general location, but information to locate the tunnels precisely had to come usually from local cadres and rear service personnel.
Extensive tunnel systems were found throughout the Iron Triangle- Thanh Dien forest area. Operation CEDAR FALLS demonstrated that patience is the primary weapon to use against an enemy hiding in tunnels: wait for him to run out of supplies or to get curious about where you are or what you are doing. It was some times necessary to flush the enemy out with tunnel rats or riot control agents or to seal and destroy the tunnels.
A tunnel rat team usually consisted of from six to ten men led by an officer or a noncommissioned officer. The individual in charge had the responsibility of drawing a sketch of the underground complex from information relayed from the team members within the tunnel. The lead element of the tunnel rat team was usually armed with a pistol equipped with a silencer (to fire in a tunnel without a silencer was to risk broken eardrums), hand telephone or "skull mike," flashlight, compass, and probe. One of the major problems in tunnel reconnaissance was that of communications. The skull mike (a transmitter strapped to the back of the skull) often became inoperative after a short period. In addition, the heavier U.S. communications wire which had to be used in lieu of the scarce lightweight Canadian assault wire added considerable weight and bulk to the team. Lack of fresh air was also a problem for the men when deep in the tunnels. The "Mighty Mite" (an air compressor with blower) or an auxiliary helicopter engine rigged with a 50 to 100 foot length of hose was often employed to force fresh air into the tunnel systems.
The job of a tunnel rat was difficult at best. Hot, dirty, and gasping for breath, he squeezed his body through narrow and shallow openings on all fours, never knowing whether the tunnel might collapse behind him or what he might find ahead around the next turn, and sensing the jolt of adrenalin at every sound. Surely this modern combat spelunker is a special breed.
The following is a description of the search and destruction of a large tunnel complex located in the triangle approximately six kilometers south of Rach Bap and about six hundred meters to the east of Route 14.
On 21 January a Viet Cong sympathizer was apprehended by the 168th Engineers and admitted having helped dig the underground complex. A patrol was organized from the staff sections of the 1st Engineer Battalion and was led by the sympathizer to the tunnel area where he pointed out several air holes and firing ports. Further examination of the area uncovered a base camp with several tunnel entrances.
The next day, after posting security forces, a thorough search of the tunnels was begun by engineer tunnel rats with initial negative results. Then a breather hole was blown open revealing the entrance to hundreds of meters of additional tunnel. About six hundred meters into the tunnel the engineers ran into an accumulation of CS, and the exploration stopped. The many documents found in the complex were taken to the G-2 of the 1st Division; upon evaluation of the papers, the G-2 determined that the search of the tunnel complex should be continued.
Next day the engineer tunnel rats returned accompanied by their counterparts from the attached chemical platoon. After exploring an additional 800 meters of tunnel, they found and removed a trapdoor, disclosing additional chambers and documents. Over one kilometer of tunnel had now been uncovered. Further exploration revealed an exit leading to another enemy base camp.
The exploration continued the following day, and more documents were uncovered and evacuated. As the tunnel rats crawled through the complex, they heard enemy voices. A CS grenade thrown by the team flushed five Viet Cong from the tunnel; they were captured as they scrambled out. Above ground; the security elements found a former hospital base camp complex 300 meters north of the camp discovered the previous day, and an investigation of tunnels of this complex was begun.
Early the next morning, the fourth day of exploration, the tunnel rats returned to the former hospital complex. Five huts were unearthed, each dug into the ground so that the roof was at ground level. Medical textbooks and notebooks, small quantities of medicine, and medical instruments were discovered in the 300 meters of rooms and chambers. The tunnel team returned to the second tunnel complex where the Viet Cong had been flushed, but CS in the tunnel prevented further exploration. Tunnel destruction personnel from the 168th Engineers arrived that afternoon and remained at the overnight position.
On 26 January, the day CEDAR FALLS terminated, the tunnel destruction team left for the former hospital complex and the exploration team returned to the "CS tunnel" complex. Using conventional demolitions and acetylene equipment, the team rigged the hospital complex for destruction after receiving word that no additional information had been found by those combing the underground labyrinth. The charges were detonated at noon; after the explosion, large cracks could be seen on the surface for a distance of approximately two hundred meters. The team then moved to the second tunnel complex and, again using a combination of conventional demolitions and acetylene, destroyed it.
Because of the numerous enemy underground complexes discovered, there were too many burrows for the few trained tunnel rats to explore. Volunteers from the 1st Engineers and other units often took on the task of exploration and destruction. As would be expected, the results when using trained, experienced, and properly equipped personnel were much more valuable-and far safer -than those gained through volunteers. Unless the tunnel was mapped as it was explored, the engineers who were to destroy the tunnel were required to go back in and map it, duplicating effort. There were also instances in which two teams were in a tunnel at the same time with neither team knowing of the other's presence. Luckily, no one was shot by mistake.
A new method of tunnel destruction was developed and used during CEDAR FALLS. It consisted of filling a tunnel with acetylene gas-forced in by blowers-then igniting the gas by demolition charges. Acetylene alone was found excellent for destroying tunnels with not more than seven feet of overhead cover. With deeper tunnels destruction was increased through the use of conventional demolitions in conjunction with the acetylene. Thirty-pound charges of TNT and 40-pound cratering charges were placed at critical locations (rooms, tunnel junctions, exits, and entrances) in the complex. These charges were dual primed, connected in series by detonation cord, and fired electrically. When detonated, the conventional charges acted as booster charges for the acetylene. These experiments, using high explosives and acetylene together, proved very effective on tunnels as much as fifteen to twenty feet below the surface.
During Operation CEDAR FALLS the 1st Engineers and attached units discovered literally helicopter loads of documents, records, and plans, many of which belonged to the Viet Cong intelligence section of Military Region IV from 1963 through 1966. The documents listed the strengths of Viet Cong units, the names of their members, and the towns and villages in which they operated; disclosed some of their meeting places; and revealed a great amount of information on exactly how the enemy operated and what his future plans were. In addition to intelligence gathering and jungle destruction, 9,445 meters of enemy tunnels, 4 villages, 27 base camps, 60 miscellaneous bunkers, and other facilities were destroyed by the engineers.
The Engineer Navy
The problem of sealing the confluence of the Saigon and Thi Tinh Rivers in order to prevent the escape of the Viet Cong by water during CEDAR FALLS resulted in another new approach to counterinsurgency warfare, an engineer "navy." The initial plan to deny this escape route to the enemy was to place a force on the banks of each of the rivers. The force would be armed with the newly acquired "quad-.50" machine guns (four heavy machine guns that traverse from a single pedestal and which are fired simultaneously by one gunner). General DePuy believed this mission could be more efficiently accomplished by installing the quad-.50's on platforms placed in the river. The engineers agreed and were given the job.
On 3 January Company E, 1st Engineer Battalion, was directed to procure and load the materials for two rafts to support the weapons and to move the materials to the Vietnamese Engineer School at Phu Cuong, twelve kilometers downstream from the juncture of the Saigon and Thi Tinh Rivers. There each raft was built by connecting two bridge floats with aluminum decking, and a quad-.50 was mounted on each of the platforms. The construction was completed in one day. Additional firepower for each raft was provided by six .30 caliber machine guns, and provision was made for riflemen and grenadiers behind sandbags to be on both the floats and the platform. Eventually dubbed Monitors, each raft was propelled by a 27-foot utility boat.
The navy also included two armed utility boats and several river patrols using pneumatic assault boats. The river patrols consisted of fifteen men: two engineers and thirteen infantrymen. One engineer operated the boat while the other secured it during loading and unloading.
Early on 5 January, with a command helicopter overhead, the engineer flotilla left Phu Cuong and moved up the Saigon River. Approximately two kilometers from its destination, lead elements experienced sniper fire which was immediately countered by machine guns from the rafts and the helicopter; four enemy were killed. By nightfall the rafts were in position at the confluence of the rivers; one raft tied to the east bank and the other anchored in midstream. While the Monitors remained in the same general vicinity for most of the operation, the utility and assault boats actively patrolled the rivers. All Vietnamese river traffic was checked and some prisoners taken. In addition the boats ferried supplies to outposts along the river. The navy of the 1st Engineers proved to be a great asset during CEDAR FALLS.
Chemical Operations
During CEDAR Fates the chemical sections of both the 1st Division and 173d Airborne Brigade were used to achieve excellent results in combat operations and in denying materiel and facilities to the enemy.
On 8 January the 1st Division chemical section conducted an experimental drop of 55 gallon drums of CS munitions from a CH-47 (Chinook) helicopter in the Thanh Dien forest in the 3d Brigade's area of operation. On 13 January another drop of thirty drums of CS set to explode at treetop level was made on a linear target approximately fifteen hundred meters long just south of Artillery Base I. Excellent functioning of the explosives and coverage of the target were reported by the Air Force forward air controller observing the drop. On 16 January another 30-drum drop was made on an enemy base camp outside of the CEDAR FALLS operational area. To produce better results on this broad target, two passes were made forming an X with fifteen drums dropped on each pass. Good coverage was again reported. Two more drops were made outside the CEDAR Fates area the next day, again with excellent results. Such drops, when made under controlled conditions in territory in friendly hands, kept the enemy from entering the area of the drop for many days unless he was masked.
The chemical sections were also very active and effective in denying use of captured rice to the enemy. When conditions permitted, the rice was removed from the area. However, in some cases, in view of the large tonnages involved as well as the location of the rice, removal was impossible. For example, on 12 January 450 tons of rice in 100 pound bags, located in eight different caches, were destroyed by the chemical personnel of the 1st Division. To contaminate the rice, a hole was made in the middle of the cache and two 40 pound cratering charges were placed in the hole and detonated. The explosion caused the bags to burst and spread the rice over a wide area. Eight-pound bags of CS crystals were then placed in and around the area, linked with detonating cord, and exploded simultaneously. This system was often and effectively used during the operation.
Flamethrowers were also employed during Operation CEDAR FALLS for land clearing and against entrenched enemy troops. Flamethrowers provided the best means of destroying the windrows of trees and brush caused by jungle clearing operations. The flamethrower equipped tracked vehicles of the 1st Squadron, 4th Cavalry, were used to burn the green jungle which had been cut. It was found that 2,600 gallons of diesel fuel, 1,500 gallons of gasoline, and 1,500 pounds of chemicals were required to consume four windrows, each 50 meters long. This expensive operation was used rather sparingly. The 2d Brigade also employed flamethrowers to assist in the capture of Viet Cong located in bunkers and tunnels. The flamethrowers reduced the amount of oxygen in the tunnels, to say nothing of producing a significantly adverse psychological effect on the enemy.
The main support of the tunnel search effort by the chemical sections, in addition to the actual tunnel rat teams, consisted of providing different types of air blowers for various uses. One use was to blow smoke into tunnels which had been located (especially those with extremely small diameters which were impractical or too difficult to search) to flush out any Viet Cong and to locate other entrances, gun ports, or breathing holes. The Buffalo Turbine, a powerful blower, was often used for this purpose along with 30-pound smoke pots. To assist in locating the smoke exiting the tunnels, observation helicopters as well as troops scouted the area. Because the smoke did not linger, the tunnels could be flushed by the blowers with relative ease so that tunnel rats could almost immediately search the tunnel. On 19 January this kind of smoke operation caused seven Viet Cong to flee a tunnel in the area of operations of the 2d Battalion, 503d Infantry. All were immediately apprehended, suffering from the effects of smoke inhalation. However, after an hour of flushing the tunnel with fresh air, a tunnel rat team was able to search the tunnel with no difficulty. At times the blowers were also used to fill the tunnels with CS.
The Army engineers and chemical teams contributed significantly to the task of destroying the enemy's facilities in the Iron Triangle and making its future use difficult. As Time magazine put it as CEDAR FALLS was drawing to a close, "If the U.S. has its way, even a crow flying across the Triangle will have to carry lunch from now on."
During its 19-day duration CEDAR FALLS compiled some im-pressive statistics. U.S. and South Vietnamese forces accounted for nearly 750 confirmed enemy dead and 280 prisoners. In addition, there were 540 Viet Cong Chieu Hoi ralliers, 512 suspects detained, and 5,987 refugees evacuated. Enemy equipment losses were 23 crew-served weapons, 590 individual weapons, and over 2,800 explosive items such as mines, grenades, and mortar and artillery rounds. Over 60,000 rounds of small arms ammunition were captured, as were many miscellaneous items of equipment, including over 7,500 uniforms. Some 1,100 bunkers, 525 tunnels, and over 500 structures were destroyed. Captured were 3,700 tons of rice- enough to feed 13,000 troops for a full year- and more than a half million pages of assorted documents.
U.S. battle losses totaled 72 killed, 337 wounded; those for the South Vietnamese, 11 killed and 8 wounded. U.S. equipment lost included 1 tank and 3 armored personnel carriers (APC's). Damage was sustained by 3 tanks, 9 APC's, 1 tankdozer, 2 quarter-ton trucks (jeeps), and 2 light observation helicopters. The South Vietnamese lost 3 individual weapons.
In addition, eleven square kilometers of jungle were cleared and many miles of road in the area were made passable. These roads, the landing zones cleared, and the swaths cut at intervals through the jungle would all make any future penetration of the area much simpler.
As had been expected, main force elements were contacted only rarely. The 1st, 7th, and 8th Viet Cong Main Force Battalions of Military Region IV did not conduct an organized defense of their areas, apparently having been directed to disperse and avoid con-tact. Task Force DEANE did report prisoners taken from the 61st Local Force Company of the Phu Loi Battalion and from small rear services elements.
A review of the interrogation reports of those who rallied, were taken prisoner, or detained indicated that the majority were from Viet Cong infrastructure in the area. Over three hundred of the ralliers and prisoners were from local guerrilla units, primarily from Ben Cat District. Personnel from combat support elements, such as farmers and laborers, accounted for the second largest category, about 25 percent. Only a few top-level cadres were identi-fied in interrogation reports, including an executive officer of Tay Ninh Military School, a captain from the Military Region IV political staff section, a lieutenant from a small guard unit, and two North Vietnamese political cadres, including the mathematics professor schooled at Peking University.
It appeared from the near-total absence of enemy acts of sabo-tage or attacks on government posts in or around Saigon during the operation that the grasp of the infrastructure upon the former inhabitants of the Iron Triangle area had been severely impaired. General Westmoreland, in commenting on Cedar Falls during a Mission Council meeting, stated that the operation had been a very disruptive one for the enemy in the Iron Triangle area. He added that it had been very impressive in its results, being the first operation in which the number of enemy captured and detained equaled the number of enemy killed.
CEDAR FALLS was to be the largest and most significant operation to this point in the war.
In addition, eleven square kilometers of jungle were cleared and many miles of road in the area were made passable. These roads, the landing zones cleared, and the swaths cut at intervals through the jungle would all make any future penetration of the area much simpler.
As had been expected, main force elements were contacted only rarely. The 1st, 7th, and 8th Viet Cong Main Force Battalions of Military Region IV did not conduct an organized defense of their areas, apparently having been directed to disperse and avoid con-tact. Task Force DEANE did report prisoners taken from the 61st Local Force Company of the Phu Loi Battalion and from small rear services elements.
A review of the interrogation reports of those who rallied, were taken prisoner, or detained indicated that the majority were from Viet Cong infrastructure in the area. Over three hundred of the ralliers and prisoners were from local guerrilla units, primarily from Ben Cat District. Personnel from combat support elements, such as farmers and laborers, accounted for the second largest category, about 25 percent. Only a few top-level cadres were identified in interrogation reports, including an executive officer of Tay Ninh Military School, a captain from the Military Region IV political staff section, a lieutenant from a small guard unit, and two North Vietnamese political cadres, including the mathematics professor schooled at Peking University.
It appeared from the near-total absence of enemy acts of sabotage or attacks on government posts in or around Saigon during the operation that the grasp of the infrastructure upon the former inhabitants of the Iron Triangle area had been severely impaired. General Westmoreland, in commenting on Cedar Falls during a Mission Council meeting, stated that the operation had been a very disruptive one for the enemy in the Iron Triangle area. He added that it had been very impressive in its results, being the first operation in which the number of enemy captured and detained equaled the number of enemy killed.
In analyzing CEDAR FALLS, General Seaman discussed the operation from several aspects. With respect to surprise, he wrote:Security in planning and deception in deployment resulted in surprising the enemy. The light initial contact and the lack of a well-coordinated defense indicated that not only did the enemy not expect our attack but was unable to react when it came. The final casualty figures show that he had been in the Iron Triangle in considerable strength, despite his weak defense.
General Seaman pointed out that application of the principle of mass had quickly and effectively sealed and thoroughly searched the area of operations by using a higher troop density than had ever before been used or been possible. This greatly improved the effectiveness of cordon and search tactics and was reflected in the high proportion of Viet Cong ralliers. "Not being able to hide or escape," he indicated, "their choice was to surrender."
General Knowles of the 196th Brigade highlighted another factor which contributed to more ralliers than before: CEDAR FALLS was a longer operation than most.
Operation CEDAR FALLS demonstrated the value of extended operations within VC controlled areas. The length of the operation gave the small unit commanders and the troops time enough to become familiar with the terrain, as well as the VC situation. Unlike many other operations where troops go into an area for two or three day search and destroy mis-sions, Cedar Falls provided the much needed continuity of effort to effectively accomplish the mission.
General Knowles also directed the following comments at the critics of mechanized units being used in counterinsurgency operations: Mechanized infantry has proven to be highly successful in search and destroy operations. With their capability for rapid reaction and firepower, a mechanized battalion can effectively control twice as much terrain as an infantry battalion. Rapid penetrations into VC controlled areas to secure LZ's for airmobile units provides an added security measure for aircraft as well as personnel when introducing units into the combat zone. The constant movement of mech units back and forth through an area keeps the VC moving and creates targets for friendly ambushes and artillery and air.
In summarizing the effects on the enemy, General Seaman said: (1) A major portion of the enemy's base and control center for operation against the Capital Military District has been destroyed. This repre-sents the loss of an investment of twenty years. The enemy's offensive capability against the Capital Military District has been reduced by loss of personnel, equipment and facilities.
(2) Over 3,700 tons of rice have been captured or destroyed. . . .More significant than the loss itself is the resultant diversion of manpower to reconstitute his stores.
(3) All of the civilian inhabitants of the area, some 6,000 plus their livestock were evacuated. This will deny the enemy food, manpower, revenue, transportation and intelligence.
(5) Realization of the seriousness of these losses by the leadership in North Vietnam, COSVN and the VC-dominated populace will have a serious psychological impact.
From every aspect, the enemy had suffered a great defeat. In the words of General Seaman, they would now have to "re-evaluate the relative capabilities of their forces as opposed to ours."
In his analysis of Cedar Falls, General Seaman also commented favorably upon another key area, the working relationship between U.S. and South Vietnamese forces:
Cooperation between U.S. and Vietnamese military and civilian agencies was excellent. This was particularly true in the evacuation of the civilian population. Both the ARVN airborne units and the River Assault Groups provided invaluable assistance in securing and transporting the refugees. Civilian and military personnel of both nations worked in close harmony to organize and build the PHU CUONG refugee camp on very short notice. On the purely military side, ARVN units contributed sig-nificantly to the effectiveness of the cordon. The ARVN River Assault Groups made a unique contribution by their patrolling along the river lines.
General DePuy, in his analysis of Operation CEDAR FALLS, stated: Operation CEDAR FALLS was long overdue. The Iron Triangle and nearby village of BEN SUC had been lucrative targets for some time. How-ever, this was the first time sufficient forces and equipment were available to properly execute such an undertaking.
The Triangle had been a notorious VC haven. From its confines attacks were launched on the surrounding area, and VC control over such areas was uncontested. Ralliers confirmed that the Triangle contained numer-ous tunnels and bunkers and huge stores of foodstuffs and equipment. Continual bombing and artillery fires certainly disrupted VC activity, but civilian occupants in the area hampered free-fire activities. Addition-ally, B-52 strikes and artillery bombardment could not be exploited with ground troops. There were simply no access routes, air or ground, into the heart of the Triangle. The few existing ox cart roads and foot trails were heavily mined and booby trapped. The 100 square kilometers of the Iron Triangle provided a secure jungle haven which no one division could seal, search and destroy.
We had no idea at the beginning that Operation CEDAR FALLS would turn out to be the most significant operation thus far conducted by the 1st Infantry Division. It is most significant in many respects. First of all, it was aimed at the headquarters, Military Region IV. This head-quarters is responsible for operations in and around SAIGON. The headquarters directed attacks on TAN SON NHUT and on U.S. troop billets in SAIGON itself.
For the first time in the history of the war in Vietnam, infantry-engineer bulldozer teams cut their way through the jungle, finding and destroying base camps, creating landing zones, pushing back the jungle from roads which can now be used for rapid repenetration of the area. One entire jungle area was completely eliminated. All in all, the engineers cut down 9 square kilometers of solid jungle. This is a technique which will be used again in the penetration of other VC war zones and base areas- a technique pioneered by the 1st Division. Everyone who worked with the engineers recognizes the tremendous contribution they made to the success of the operation.
In addition to the destruction of the base area of Military Region IV, the most significant and unexpected result was the surrender of so many Viet Cong. This has never happened before in the war in Vietnam, and in this area, at least, is a reflection of the complete breakdown in confidence and morale on the part of the VC.
Although I do not expect the war to end quickly, I believe this has been a decisive turning point in the III Corps area; a tremendous boost to the morale of the Vietnamese Government and Army; and a blow from which the VC in this area may never recover.
In nineteen days, II Field Force, Vietnam, had converted the Iron Triangle from a haven to a sealed battleground and then to a military no-man's-land. Years of work spent tunneling and hoarding supplies were nullified. The civilian population was removed, making any enemy attempt to rebuild doubly difficult. Concealment, particularly along lines of communication, was stripped away, exposing the area to future surveillance. Finally, the area was designated a specified strike zone so that it could be interdicted with ease should the enemy attempt to rebuild. A strategic enemy base had been decisively engaged and destroyed.
By all accounts Cedar Falls had to be one of the significant operations in the Vietnam War. Certainly it was the significant operation in January 1967; however, that did not mean that there were no operations being conducted in other areas of Vietnam. In fact, in the III Corps Tactical Zone itself there were eighteen separate major military operations conducted during that month, fifteen of them resulting in contact with the enemy.
Intelligence sources summarized the situation in the III Corps area as Cedar Falls came to a close as follows, perhaps providing some insight into what the future might have in store:
During Operation Cedar Falls the VC losses in personnel were the equivalent of three battalions. These losses however, were widely scattered and cannot be attributed to specific units. . . . [This defeat] coupled with the recent defeat of [9th VC Division] regiments with resultant loss of major supply stockpiles in the Iron Triangle, Tay Ninh and Phuoc Tuy Provinces indicate the VC will require time for resupply, replacement, retraining, and re-indoctrination. To gain time the VC will, in all probability adapt their Winter Campaign Plan to divert attention from Tay Ninh and other areas selected for reoccupation.
But Generals Westmoreland and Seaman and II Field Force, Vietnam, were not going to give the enemy the time they required or the opportunity to divert attention from the areas in which they had been hit. On the horizon loomed JUNCTION CITY, an operation which was to carry the war deep into enemy sanctuaries in War Zone C for an extended period.