Operation Crimp
Encyclopedia
Operation Crimp also known as the Battle of the Ho Bo Woods
, was a joint US-Australian military operation during the Vietnam War
, which took place 20 kilometres (12.4 mi) north of Cu Chi in Binh Duong Province
, South Vietnam
. The operation targeted a key Viet Cong headquarters that was believed to be concealed underground, and involved two brigades under the command of the US 1st Infantry Division, including the 1st Battalion, Royal Australian Regiment
(1 RAR) which was attached to the US 173rd Airborne Brigade. Heavy fighting resulted in significant casualties on both sides, but the combined American and Australian force was able to uncover an extensive tunnel network covering more than 200 kilometres (124.3 mi).
The operation was the largest allied military action mounted during the war in South Vietnam to that point, and the first fought at division
level. Despite some success, the allied force was only able to partially clear the area and it remained a key communist transit and supply base throughout the war. The tunnels were later used as a staging area for the attack on Saigon during the 1968 Tet offensive before they were largely destroyed by heavy bombing from American B-52 bombers in 1970, ending their utility.
William Westmoreland
. At first the Americans had adopted a cautious strategy, applied to the strictly limited role of base defence by US Marine
units. This was abandoned in April 1965, and replaced by a new 'enclave strategy' of defending key coastal population centres and installations. This strategy required the introduction of nine additional US battalion
s, or 14,000 troops, to bring the total in Vietnam to 13. Allied nations of the Free World Military Forces
were expected to contribute another four battalions. Westmoreland planned to develop a series of defensive positions around Saigon before expanding operations to pacify the South Vietnamese country-side and as a result a number of sites close to Viet Cong dominated areas were subsequently chosen to be developed into semi-permanent divisional-level bases. Such areas included Di An which was intended to become the headquarters of the US 1st Infantry Division, while the US 25th Infantry Division would be based in the vicinity of Cu Chi. However, large-scale military operations to clear the intended base areas had to wait until the dry season.
Australia's growing involvement in Vietnam reflected the American build up. In 1963, the Australian government had committed a small advisory team, known as the Australian Army Training Team Vietnam
(AATTV), to help train the South Vietnamese forces. However, in June 1965 the decision to commit ground troops was made, and the 1st Battalion, Royal Australian Regiment—originally commanded by Lieutenant Colonel Ivan 'Lou' Brumfield—was dispatched. Supporting 1 RAR was 1 Troop, A Squadron, 4th/19th Prince of Wales's Light Horse
with M-113 Armoured Personnel Carriers
, artillery from 105 Field Battery, Royal Regiment of Australian Artillery
and 161 Field Battery, Royal New Zealand Artillery, and 161 Reconnaissance Flight
operating Cessna 180
s and Bell H-13 Sioux light observation helicopters; in total 1,700 personnel. The Australian units were attached to the US 173rd Airborne Brigade under the command of Brigadier General
Ellis W. Williamson in Bien Hoa
and operated throughout the III Corps Tactical Zone
to help establish the Bien Hoa-Vung Tau enclave. Although logistics and resupply were primarily provided by the Americans, a small logistic unit—1st Australian Logistics Company—was situated at Bien Hoa airbase
. Unlike later Australian units that served in Vietnam, which included conscripts
, 1 RAR was manned by regular personnel
only. The battalion commenced operations in late June 1965 and initially focussed on defeating the Viet Cong's wet season offensive. During this time US 173rd Brigade, including 1 RAR, conducted a number of operations into War Zone D—a major communist base area at the junction of Phuoc Long, Long Khanh, Bien Hoa and Binh Duong provinces. Operations were also conducted in the notorious Iron Triangle
, formed by the confluence of the Saigon
and Thi Tinh rivers and Route 7, where they fought a number of significant actions including the Battle of Gang Toi
in November, before launching Operation Marauder on the Plain of Reeds in the Mekong Delta
on New Years Day 1966.
were believed to contain the political-military headquarters of the communist 4th Military Region, which controlled all Viet Cong activity around the South Vietnamese capital, Saigon. Although its precise position was unknown, it was believed to be concealed in an extensive underground bunker system. Agents' reports, the interrogation of prisoners, and aerial surveillance all pointed to the presence of this vital communist facility. The headquarters itself was believed to be located in a 31 square kilometres (12 sq mi) area of jungle and marshland, and to have four entrances guarded by a Viet Cong Regional Force company, while two Main Force battalions were also thought to be in the vicinity to afford additional security. Communist units detected in the Ho Bo Woods by allied intelligence included the C306 Local Force Company, 3rd Quyet Thang Battalion and 7th Cu Chi Battalion.The PAVN official history written after the war mentions only C306 Local Force Company specifically by name during its recount of the battle, although it does allude to the presence of other units. See Van Thai 2002, p. 176.Quyết Thắng means "resolve to win". The commander of the Cu Chi Battalion was later identified after the war as Captain Nguyen Thanh Linh. In total, local communist defensive strength was believed to include 1,000 men.
In response, a large American 'search-and-destroy' operation was launched in January 1966, involving more the 8,000 troops commanded by the US 1st Infantry Division under Major General
Jonathan O. Seaman
, including the US 3rd Infantry Brigade, 1st Infantry Division and the US 173rd Airborne Brigade, which was attached to the division for the operation; in total six battalions plus supporting arms. Still attached to the US 173rd Brigade was the Australian battalion, 1 RAR—by now commanded by Lieutenant Colonel Alex Preece—with 105 Field Battery in direct support, as well as engineers from 3rd Field Troop, Royal Australian Engineers and the M113s from the Prince of Wales Light Horse. At the time it was the largest military operation mounted in South Vietnam, being the first divisional offensive to date. Preceded by a heavy aerial bombardment, the scheme of manoeuvre envisioned an airmobile assault by the US 173rd Brigade in the north and west, while the US 3rd Infantry Brigade would seal off the area to the south, in preparation for a sweep designed to push trapped communist forces eastwards against the Saigon River. 1 RAR's role was to establish a blocking position in a village beside the river on the northern flank of the brigade's area of operations. In order to achieve tactical surprise, the operation was launched immediately following Operation Marauder, with the Australians and Americans redeployed by air.
Prior to the assault, the 1 RAR Operations Officer, Major John Essex-Clarke, conducted an aerial reconnaissance of the proposed Landing Zone—known as LZ June—on 7 January. Observing a lack of ground foliage, he was concerned about the possibility of extensive Viet Cong defensive works close to the LZ, and with the support of Williamson the landing zone was subsequently switched to a less-exposed location. The original plan would have seen 1 RAR inserted directly on top of a heavily defended bunker system, and would have likely resulted in heavy casualties. Captain Alec MacGregor, the commander of the 3rd Field Troop, was of the opinion that the "decision almost certainly saved hundreds of Australian lives."
The battle began at 09:30 on 8 January with heavy American preparatory fire from artillery, as well as napalm
and airstrikes from B-52
bombers which resulted in significant defoliation. Soon after the airmobile operation commenced with the first American units being inserted by helicopter to the north, west and south. The US 3rd Infantry Brigade—under the command of Colonel William Brodbeck—was subsequently inserted by helicopter and by road. The brigade headquarters and command element departed Di An in convoy and reached Trung Lap on the western boundary of the brigade's area of operations by midday. Concurrently, two battalions were inserted by helicopter to the south-west, one blocking the south side of the Ho Bo Woods while the other conducted a sweep. The Americans were in contact almost immediately, although the engagements were generally small scale, or involving snipers. Meanwhile the brigade's third battalion moved by road to Trung Lap and then moved on foot to its assigned search area.
In the north, 1 RAR was inserted into its new landing zone—LZ March—3 kilometres (1.9 mi) to the south-west. With B Company securing the site, the battalion moved on foot to the line of departure but not before they were mistakenly engaged by US helicopter gunships and artillery fire. However, after the Australians established communications, the shelling was halted and they began their advance. No sooner had the lead elements—D Company under the command of Major Ian Fisher—emerged into the cleared area that was originally to have been used as the battalion's LZ, when the forward platoon
came under fire from Viet Cong positions in the tree-line on the north-east corner. In the action which followed, six Australians from 12 Platoon were wounded, including platoon commander Lieutenant Jim Bourke, who was shot through the jaw but remained in command until he passed out from loss of blood. Meanwhile two medics who attempted to move forward to treat the casualties were themselves shot and killed.
Preece moved to push his other companies around each flank of D Company, and towards the battalion's original blocking position. Soon they were also in contact with small groups of Viet Cong from positions behind trees and in bunkers, while others popped up from spider holes and tunnel entrances; it became apparent to the Australians that they had stumbled across a significant Viet Cong force in extensive fortifications, sufficient to hold a battalion. B Company, under the command of Major Ian McFarlane, also uncovered a small dug-in hospital with simple transfusion equipment, documents and bandages. Meanwhile, the remaining battalions of the US 173rd Airborne Brigade had also been inserted. The 1st Battalion, 503rd Infantry Regiment flew into LZ April at 12:00, while 2/503rd Battalion arrived at LZ May at 14:30. With the insertion going largely according to plan, the brigades began their advance eastwards. Converging on the suspected location of the communist headquarters, a thorough search of the area yielded little, and it was believed that the Viet Cong had withdrawn earlier in response to the initial Australian advance.
Amid strong resistance, the Australians were made to fight their way through the maze of bunkers, punji stakes
and booby traps but they were eventually able to force a Viet Cong regional force company to withdraw as they continued their advance. The area was heavily seeded with trip wires connected to shells and grenades dangling from branches, one of which blew McFarlane and several of his men off their feet. The defenders subsequently withdrew, with 7th Cu Chi Battalion forced north and 3rd Quyet Thang Battalion to the east. Suspecting they were being drawn into a trap—as one of the American battalions of the brigade had been previously during Operation Hump
—the Australians moved into a tightly defended perimeter before dark and waited for the communists to counter-attack. As night fell, movement was detected along a trench on the C Company perimeter when a squad of Viet Cong attempted to infiltrate the Australian position. Initially believing the movement to be another Australian patrol that had just departed on a clearing patrol, the machine-gunner on sentry duty finally opened fire at the last safe moment, killing one of the infiltrators at point-blank range and wounding a number of others before they withdrew.
Minor actions continued into the night, with small groups of Viet Cong able to pop up undetected and then disappear at will from within the Australian defensive position. The searching units were unable to locate Viet Cong in large numbers but experienced a significant number of sudden engagements and ambushes throughout the day, and it became clear that the communists were using tunnels for movement and concealment. Preece suspected that the area was honeycombed with tunnels and that the communist headquarters that he had been tasked to destroy was in fact located beneath the feet of the battalion. The Australians were the only battalion in the US 173rd Brigade to strike significant resistance, and by the end of the first day 1 RAR had suffered a total of three killed and 15 wounded, while the artillery Forward Observer from 105 Field Battery had also been killed. The battalion spent a sleepless night and in the early hours of the morning there were a number of short exchanges of fire as small groups of Viet Cong returned to the area. Not wanting to fire the machine-guns for fear of giving their positions away or hitting friendly troops, the Australians resorted to using grenades forward of the perimeter. Meanwhile, in the US 3rd Infantry Brigade area of operations contact had been light, with only six Viet Cong killed.
for his leadership.
Originally constructed in 1945 by the Viet Minh
during the fighting with the French in the First Indochina War
, the tunnels at Cu Chi had taken decades to build but later had lain dormant after the war until 1960, when they were reactivated. Since then they had endured constant bombing, all the while being expanded. By 1965 they formed an underground maze of passages, fighting tunnels, meeting rooms and food caches, stretching from Saigon to the Cambodian border. Given their headquarters function, the tunnels were equipped with an array of communications and medical facilities and were defended by interlocking arcs of fire
and connecting fire tunnels. Dug into hard clay which had largely protected them from American bombing, some trenches were reported as being more 1.8 metres (5.9 ft) deep, and some tunnels as long as 460 metres (503.1 yd), while numerous side tunnels led from the main tunnels. In places the system was between one, two and even three levels deep. The network was so extensive that they were rumoured to be able to hold 5,000 men, many of whom lived underground for up to six months at a time. On seeing the tunnels one American soldier described them at the time as "the New York subway".
In the southern area of operations, the US 3rd Infantry Brigade was making slow progress, with the Viet Cong using hit-and-run
and ambush
tactics to inflict casualties on the Americans, before withdrawing into the sanctuary of their underground tunnels. On 9 January, the Americans located and destroyed a cache of medical supplies, as well as a large amount of rice and a small hospital, as well as capturing 30 Viet Cong during a series of skirmishes. To the north, while 1 RAR searched the tunnel complex the American battalions of the US 173rd Airborne Brigade continued to sweep their area of operations, with a number of friendly fire
incidents complicating their task. Both the 1/503rd and 2/503rd Battalions searched eastward toward the Saigon River and, although they continued to find supply caches and abandoned positions, they were involved in only minor skirmishes with the Viet Cong. Concealed in well-camouflaged ambush positions however, the communists inflicted a number of casualties on the Americans. Only one Viet Cong was killed during the fighting, bringing the total for the operation to just 22. Despite the large number of US troops involved they had experienced only limited contact to that point, and criticism of the operation consequently began to mount in the American media.
and the Australians from the Prince of Wales Light Horse commenced a combined search operation and fought communist snipers and small groups throughout most of the day. At 14:00 a number of Viet Cong dug-in in trenches were encountered, and following a series of air-strikes and artillery barrages, the cavalry and the Australian M113s swept the area during which several Australians were slightly injured by a misdirected US Navy air-strike. Sixteen Viet Cong bodies were subsequently recovered, and another 60 were believed to have been killed but had been removed from the battlefield.
Williamson subsequently ordered the 1/503rd Battalion—under the command of Lieutenant Colonel John Tyler—to change the direction of its advance. During the morning the battalion had conducted platoon-sized patrols south, south-west and west, locating a well-constructed defensive position, including bunkers and trenches connected by tunnels. With no contact as yet made with the Viet Cong, the battalion prepared to move to a new AO in the north by 13:30. During this move the battalion, and armour from Troop D, 16th Cavalry Regiment
, engaged a dug-in Viet Cong Main Force company less than 2000 metres (2,187.2 yd) west of the Australians. Following air-strikes and heavy artillery bombardment the communists withdrew, leaving 29 dead during a sharp engagement. The 2/503rd Battalion had also sent out a number of squad-sized patrols during the day, but no recent signs of Viet Cong activity were found, and only minor sniper fire encountered. However, like the Australians, the American paratroopers also uncovered a large number of tunnels and other fortifications.
Meanwhile, the US 3rd Brigade continued to make slow progress and, despite reaching the banks of the Saigon River by 10 January, only a few brief glimpses of the Viet Cong had been made. A small base camp was discovered and destroyed however, while another battalion captured more than 10 tons of rice and 15 bales of cotton
. The following day the Americans found and destroyed more bunkers and a number of houses and sampans, as well as quantities of supplies and food. They also uncovered a tunnel complex and a quantity of maps, charts and documents, although still little resistance was met. During these actions the Americans lost more men to booby traps than enemy fire. Advancing on a 1500 metres (1,640.4 yd) front, troops from the 1/28th Battalion—commanded by Lieutenant Colonel Robert Haldane—took a number of casualties from snipers, although the source of the fire was not immediately obvious. The Viet Cong attempted to avoid a set piece battle, opting instead to disperse into small groups to fight from their spider-holes and tunnels and only choosing to engage the Americans at close range with small arms, which included old Russian K-44 rifles. Despite suffering a number of casualties the Americans continued to advance, calling in artillery fire. Such tactics proved largely ineffectively though and the Commanding Officer of 2/28th Battalion, Lieutenant Colonel George Eyster, was himself shot and killed by a sniper during the fighting. Regardless, after receiving word of the discovery of the tunnels by US 173rd Airborne Brigade to their north, the brigade began another sweep.
The US 3rd Brigade subsequently also uncovered a significant tunnel complex, after Sergeant Stewart Green from 1/28th Battalion accidentally sat down on a nail and uncovered a trap door on 11 January. Volunteering to enter the tunnel, Green then located an underground dispensary occupied by more than 30 Viet Cong who subsequently escaped. Later a smoke machine was used to pump smoke into the tunnel system, and this was successful in locating numerous tunnel entrances and bunkers as the smoke rose above the jungle canopy. They were the first American troops to enter the tunnels, and they proceeded to attack them with CS gas
, and later explosives. However, such tactics met with limited success with the tear gas flushing out large numbers of women and children, but few Viet Cong. Led by Green, a squad of Americans equipped with flashlights, pistols and a field telephone penetrated over 1.6 kilometre (0.994196378639691 mi) of the tunnel system before becoming involved in a fire-fight with the Viet Cong. Wearing gas-masks the Americans threw gas grenades and fought their way back to the tunnel entrance, but one soldier became lost in the darkness and Green re-entered the tunnel to find him. The Viet Cong subsequently withdrew.
Yet even as the Americans were attempting to clear the tunnels, heavy hand-to-hand fighting broke out above ground and Haldane was later awarded the Silver Star
for his actions when he rushed a bunker while under fire armed only with a pistol
, in order to give first aid to a number of wounded soldiers. His courage inspired his men to complete the assault, and ultimately helped ensure the successful evacuation of the casualties and the capture of their objective. That evening the battalions of US 3rd Infantry Brigade had completed searching their assigned area of operation, and the following morning they were withdrawn from the operation. The brigade's involvement in Crimp had been limited, losing six killed and 45 wounded, while 22 Viet Cong had been killed. It was subsequently redeployed on Operation Buckskin.
The same day, however, the Australian efforts to clear the tunnels had suffered a setback after an engineer became stuck in a trap door between one underground gallery and another, more than 2 metres (6.6 ft) below the surface. Despite the efforts of his comrades, he could not be recovered and died from asphyxiation after being overcome by a combination of tear gas, carbon monoxide, and lack of oxygen when he dislodged his respirator during the struggle to free himself. After days of living in close proximity to the enemy, the constant strain of sniper fire and the pressure of searching the tunnels was also beginning to take its toll, and a number of Australians were killed and wounded in otherwise avoidable friendly fire incidents on the evenings of 10 and 12 January. During the early afternoon of 12 January the Australians encountered a large group of armed Viet Cong during a tunnel clearance and called on them to surrender. However they failed to emerge and the tunnel was subsequently demolished, probably killing eight Viet Cong who were believed to have been entombed as it collapsed.
Meanwhile the same day Haldane ordered 1/28th Battalion to closely explore the tunnels in their area of operations, uncovering a number chambers and trapdoors defended by grenades and booby traps. A Company subsequently located another tunnel system after an American was killed by a Viet Cong soldier who suddenly appeared out of a large anthill. Later, as the 1/503rd continued to search its area with platoon-size patrols during the afternoon of 13 January, a clash between Company C and a Viet Cong platoon developed into a heavy contact. An air-strike was successfully called in by the Americans however, and a search of the area recovered 10 dead Viet Cong, while blood trails and human remains indicated that perhaps another 20 were also killed.
Fully exploring and destroying the tunnels was well beyond the allied resources available, and the decision was eventually made to call a halt to operations. Six days after it began, Operation Crimp ended, with 1 RAR returning to Bien Hoa on 14 January. By the time the operation was concluded only a fraction of the known tunnel network had been destroyed and it was not until after the war that it was learnt that the system at Cu Chi actually included more than 200 kilometres (124.3 mi) of tunnels. Although further American ground operations as well a number of heavy B52 bombing raids resulted in further damage to the tunnel complexes, the Ho Bo Woods were never occupied on a permanent basis and the Viet Cong were successful in restoring their transit and supply functions. As such, despite significant disruption, the military and political apparatus in Cu Chi remained largely intact, allowing the communists freedom of action for later operations against Saigon.
, the head of Intelligence at MACV
, visited 1 RAR during Operation Crimp.Neither Westmoreland nor McChristian referred to the operation in their end of tour reports, however. See McAulay 2007, p. 34. Allied operations against the communist tunnels had been largely ad hoc, and the Australians began to develop the earliest techniques for exploring and destroying them. Later, at least partially as a result of the success of the Australians in clearing some of the shorter tunnels, American units adopted similar tactics and created a number of tunnel-clearance teams, known popularly as Tunnel Rats.The Australian teams were originally referred to as "ferrets". See Mangold and Penycate 1985, p. 56.
Despite the losses suffered by the communists, the combined American and Australian force had only succeeded in partially clearing the area and the tunnel network it concealed, and consequently the Ho Bo Woods would remain a key communist transit and supply base throughout the war. Indeed the bulk of the communist force had successfully withdrawn intact, leaving only rear guard elements in defence, prompting the communists to also declared the operation a victory, claiming almost 2,000 American troops killed or wounded, 100 vehicles destroyed, and 50 aircraft shot down. Yet, such claims were based on estimates of casualties caused by command-detonated mines, punji sticks and other booby traps, and proved to be wildly inaccurate. In fact Operation Crimp had rattled the communists, and they subsequently ordered their units in the south to prevent the Americans from concentrating their forces in the future. Regardless it also highlighted the inherent weakness of the search-and-clear operations that would later become standard operating procedure for the US Army in Vietnam.
At the strategic level, the allied enclave strategy proved only transitory. Further setbacks led to additional troop increases to halt the losing trend, with US troop levels planned to rise from 210,000 in January to 326,000 by December 1966. In March 1966, as part of this strategy, the Australian government also increased its commitment to the ground war in Vietnam, committing a two battalion brigade—known as the 1st Australian Task Force
(1 ATF)—with armour, aviation and artillery support; in total 6,300 personnel. 1 RAR was subsequently replaced and 1 ATF was allocated its own area of operations in Phuoc Tuy Province
, thereby allowing the Australians to pursue operations more independently using their own tactics. The task force arrived between April and June 1966, constructing a base at Nui Dat
, while logistic arrangements were provided by 1st Australian Logistics Support Group
which was subsequently established at the port of Vung Tau
. Operation Crimp was 1 RAR's third and last foray into the communist heartland and following the fighting they had more than two weeks rest in Bien Hoa—their longest break from operations during the battalion's tour. However, further operations followed in the months afterwards, including the Battle of Suoi Bong Trang
on the night of 23–24 February 1966.
The Ho Bo Woods were again targeted by the Americans in January 1967, during a much larger operation known as Operation Cedar Falls
. However despite heavy casualties again being inflicted on the Viet Cong, the tunnels continued to remain a problem for the Americans and they were later used as a communist staging area for the attack on Saigon during the 1968 Tet offensive. Finally in 1970, American B-52 bombers carried out a number of heavy air-strikes on the area, dropping thousands of delayed-fuse bombs that buried deep into the ground before exploding, ending the tunnels' utility.
Ho Bo Woods
Ho Bo Woods was located in Binh Duong Province 20 km north of Cu Chi, 4 km to the west of the Iron Triangle and the Saigon River and some 56 km northwest of Saigon. The woods consisted of rubber plantations, sparse to dense woods, and open rice paddies with some extremely large...
, was a joint US-Australian military operation during the Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
, which took place 20 kilometres (12.4 mi) north of Cu Chi in Binh Duong Province
Binh Duong Province
Bình Dương is a province of Vietnam. It is located in the southeastern part of the country, immediately to the north of Ho Chi Minh City. The province was created from Song Be province on January 1, 1997.-Geography:...
, South Vietnam
South Vietnam
South Vietnam was a state which governed southern Vietnam until 1975. It received international recognition in 1950 as the "State of Vietnam" and later as the "Republic of Vietnam" . Its capital was Saigon...
. The operation targeted a key Viet Cong headquarters that was believed to be concealed underground, and involved two brigades under the command of the US 1st Infantry Division, including the 1st Battalion, Royal Australian Regiment
1st Battalion, Royal Australian Regiment
1st Battalion, Royal Australian Regiment is a regular light infantry battalion of the Australian Army. 1 RAR was first formed as the 65th Australian Infantry Battalion in 1945 and since then has been deployed on active service during the Korean War, the Malayan Emergency and the Vietnam War...
(1 RAR) which was attached to the US 173rd Airborne Brigade. Heavy fighting resulted in significant casualties on both sides, but the combined American and Australian force was able to uncover an extensive tunnel network covering more than 200 kilometres (124.3 mi).
The operation was the largest allied military action mounted during the war in South Vietnam to that point, and the first fought at division
Division (military)
A division is a large military unit or formation usually consisting of between 10,000 and 20,000 soldiers. In most armies, a division is composed of several regiments or brigades, and in turn several divisions typically make up a corps...
level. Despite some success, the allied force was only able to partially clear the area and it remained a key communist transit and supply base throughout the war. The tunnels were later used as a staging area for the attack on Saigon during the 1968 Tet offensive before they were largely destroyed by heavy bombing from American B-52 bombers in 1970, ending their utility.
Background
The initial American commitment to the war was limited to materiel and advisors only, and by 1964 there were 21,000 US advisors in South Vietnam. Yet the worsening situation led to a significant escalation of the war in 1965, with a large-scale commitment of ground troops under the command of GeneralGeneral
A general officer is an officer of high military rank, usually in the army, and in some nations, the air force. The term is widely used by many nations of the world, and when a country uses a different term, there is an equivalent title given....
William Westmoreland
William Westmoreland
William Childs Westmoreland was a United States Army General, who commanded US military operations in the Vietnam War at its peak , during the Tet Offensive. He adopted a strategy of attrition against the National Liberation Front of South Vietnam and the North Vietnamese Army. He later served as...
. At first the Americans had adopted a cautious strategy, applied to the strictly limited role of base defence by US Marine
United States Marine Corps
The United States Marine Corps is a branch of the United States Armed Forces responsible for providing power projection from the sea, using the mobility of the United States Navy to deliver combined-arms task forces rapidly. It is one of seven uniformed services of the United States...
units. This was abandoned in April 1965, and replaced by a new 'enclave strategy' of defending key coastal population centres and installations. This strategy required the introduction of nine additional US battalion
Battalion
A battalion is a military unit of around 300–1,200 soldiers usually consisting of between two and seven companies and typically commanded by either a Lieutenant Colonel or a Colonel...
s, or 14,000 troops, to bring the total in Vietnam to 13. Allied nations of the Free World Military Forces
Free World Military Forces
Free World Military Forces, or FWMF was a military force composed of a collective group of nations who sent troops to fight in Vietnam under the FWMF banner. The number of troops sent varied greatly, with nearly 50,000 from Korea, and only 10 from Spain...
were expected to contribute another four battalions. Westmoreland planned to develop a series of defensive positions around Saigon before expanding operations to pacify the South Vietnamese country-side and as a result a number of sites close to Viet Cong dominated areas were subsequently chosen to be developed into semi-permanent divisional-level bases. Such areas included Di An which was intended to become the headquarters of the US 1st Infantry Division, while the US 25th Infantry Division would be based in the vicinity of Cu Chi. However, large-scale military operations to clear the intended base areas had to wait until the dry season.
Australia's growing involvement in Vietnam reflected the American build up. In 1963, the Australian government had committed a small advisory team, known as the Australian Army Training Team Vietnam
Australian Army Training Team Vietnam
The Australian Army Training Team Vietnam was a specialist unit of the Australian Army that operated during the Vietnam War. Raised in 1962, the unit was raised solely for service as part of Australia's contribution to the war in Vietnam, providing training and assistance to South Vietnamese forces...
(AATTV), to help train the South Vietnamese forces. However, in June 1965 the decision to commit ground troops was made, and the 1st Battalion, Royal Australian Regiment—originally commanded by Lieutenant Colonel Ivan 'Lou' Brumfield—was dispatched. Supporting 1 RAR was 1 Troop, A Squadron, 4th/19th Prince of Wales's Light Horse
1st Armoured Personnel Carrier Squadron (Australia)
The 1st Armoured Personnel Squadron was an armoured unit of the Australian Army raised for service during the Vietnam War. Raised in 1965 the unit was deployed to South Vietnam in May 1966 to join the 1st Australian Task Force...
with M-113 Armoured Personnel Carriers
M113 armored personnel carrier
The M113 is a fully tracked armored personnel carrier that has formed the backbone of the United States Army's mechanized infantry units from the time of its first fielding in Vietnam in April 1962. The M113 was the most widely used armored vehicle of the U.S...
, artillery from 105 Field Battery, Royal Regiment of Australian Artillery
Royal Regiment of Australian Artillery
The Royal Regiment of Australian Artillery, normally referred to as the Royal Australian Artillery , is a corps of the Australian Army descended from the original colonial artillery units prior to Australia's federation...
and 161 Field Battery, Royal New Zealand Artillery, and 161 Reconnaissance Flight
161st Independent Reconnaissance Flight (Australia)
The 161st Independent Reconnaissance Flight was an Australian Army aviation unit. Formed in 1965 during the Vietnam War, in September that year the flight deployed to South Vietnam with two Cessna 180s and two Sioux light obersvation helicopters in order to support the 1st Battalion, Royal...
operating Cessna 180
Cessna 180
The Cessna 180 is a four- or six-seat, fixed conventional gear general aviation airplane which was produced between 1953 and 1981. Though the design is no longer in production, many of these aircraft are still in use as personal aircraft and in utility roles such as bush...
s and Bell H-13 Sioux light observation helicopters; in total 1,700 personnel. The Australian units were attached to the US 173rd Airborne Brigade under the command of Brigadier General
Brigadier General
Brigadier general is a senior rank in the armed forces. It is the lowest ranking general officer in some countries, usually sitting between the ranks of colonel and major general. When appointed to a field command, a brigadier general is typically in command of a brigade consisting of around 4,000...
Ellis W. Williamson in Bien Hoa
Bien Hoa
Biên Hòa is a city in Dong Nai province, Vietnam, about east of Ho Chi Minh City , to which Bien Hoa is linked by Vietnam Highway 1.- Demographics :In 1989 the estimated population was over 300,000. In 2005, the population wss 541,495...
and operated throughout the III Corps Tactical Zone
III Corps (South Vietnam)
III Corps was a corps of the Army of the Republic of Vietnam , the army of the nation state of South Vietnam that existed from 1955 to 1975...
to help establish the Bien Hoa-Vung Tau enclave. Although logistics and resupply were primarily provided by the Americans, a small logistic unit—1st Australian Logistics Company—was situated at Bien Hoa airbase
Bien Hoa Air Base
Bien Hoa Air Base is a Vietnam People's Air Force military airfield located in South-Central southern Vietnam about 20 miles from Saigon near the city of Bien Hoa within Dong Nai Province....
. Unlike later Australian units that served in Vietnam, which included conscripts
Conscription in Australia
Conscription in Australia, or mandatory military service also known as National Service, has a controversial history dating back to the first years of nationhood...
, 1 RAR was manned by regular personnel
Regular army
A regular army consists of the permanent force of a country's army that is maintained under arms during peacetime.Countries that use the term include:*Australian Army*British Army*Canadian Forces, specifically "Regular Force"*Egyptian army*Indian Army...
only. The battalion commenced operations in late June 1965 and initially focussed on defeating the Viet Cong's wet season offensive. During this time US 173rd Brigade, including 1 RAR, conducted a number of operations into War Zone D—a major communist base area at the junction of Phuoc Long, Long Khanh, Bien Hoa and Binh Duong provinces. Operations were also conducted in the notorious Iron Triangle
Iron Triangle (Vietnam)
The Iron Triangle was a area in the Binh Duong Province of Vietnam, so named due to it being a stronghold of Viet Minh activity during the war...
, formed by the confluence of the Saigon
Saigon River
The Saigon River is a river located in southern Vietnam that rises near Phum Daung in southeastern Cambodia, flows south and south-southeast for about 140 miles and empties into the Nha Be River, which in its turn empties into the South China Sea some 20 km north-east of the Mekong Delta.The...
and Thi Tinh rivers and Route 7, where they fought a number of significant actions including the Battle of Gang Toi
Battle of Gang Toi
The Battle of Gang Toi was fought during the Vietnam War between Australian troops and the Viet Cong. The battle was one of the first engagements between the two forces during the war and occurred when the 1st Battalion, Royal Australian Regiment struck a Viet Cong bunker system defended by...
in November, before launching Operation Marauder on the Plain of Reeds in the Mekong Delta
Mekong Delta
The Mekong Delta is the region in southwestern Vietnam where the Mekong River approaches and empties into the sea through a network of distributaries. The Mekong delta region encompasses a large portion of southwestern Vietnam of . The size of the area covered by water depends on the season.The...
on New Years Day 1966.
Prelude
Located 4 kilometres (2.5 mi) west of the Iron Triangle, the Ho Bo WoodsHo Bo Woods
Ho Bo Woods was located in Binh Duong Province 20 km north of Cu Chi, 4 km to the west of the Iron Triangle and the Saigon River and some 56 km northwest of Saigon. The woods consisted of rubber plantations, sparse to dense woods, and open rice paddies with some extremely large...
were believed to contain the political-military headquarters of the communist 4th Military Region, which controlled all Viet Cong activity around the South Vietnamese capital, Saigon. Although its precise position was unknown, it was believed to be concealed in an extensive underground bunker system. Agents' reports, the interrogation of prisoners, and aerial surveillance all pointed to the presence of this vital communist facility. The headquarters itself was believed to be located in a 31 square kilometres (12 sq mi) area of jungle and marshland, and to have four entrances guarded by a Viet Cong Regional Force company, while two Main Force battalions were also thought to be in the vicinity to afford additional security. Communist units detected in the Ho Bo Woods by allied intelligence included the C306 Local Force Company, 3rd Quyet Thang Battalion and 7th Cu Chi Battalion.The PAVN official history written after the war mentions only C306 Local Force Company specifically by name during its recount of the battle, although it does allude to the presence of other units. See Van Thai 2002, p. 176.Quyết Thắng means "resolve to win". The commander of the Cu Chi Battalion was later identified after the war as Captain Nguyen Thanh Linh. In total, local communist defensive strength was believed to include 1,000 men.
In response, a large American 'search-and-destroy' operation was launched in January 1966, involving more the 8,000 troops commanded by the US 1st Infantry Division under Major General
Major General
Major general or major-general is a military rank used in many countries. It is derived from the older rank of sergeant major general. A major general is a high-ranking officer, normally subordinate to the rank of lieutenant general and senior to the ranks of brigadier and brigadier general...
Jonathan O. Seaman
Jonathan O. Seaman
-External links:***...
, including the US 3rd Infantry Brigade, 1st Infantry Division and the US 173rd Airborne Brigade, which was attached to the division for the operation; in total six battalions plus supporting arms. Still attached to the US 173rd Brigade was the Australian battalion, 1 RAR—by now commanded by Lieutenant Colonel Alex Preece—with 105 Field Battery in direct support, as well as engineers from 3rd Field Troop, Royal Australian Engineers and the M113s from the Prince of Wales Light Horse. At the time it was the largest military operation mounted in South Vietnam, being the first divisional offensive to date. Preceded by a heavy aerial bombardment, the scheme of manoeuvre envisioned an airmobile assault by the US 173rd Brigade in the north and west, while the US 3rd Infantry Brigade would seal off the area to the south, in preparation for a sweep designed to push trapped communist forces eastwards against the Saigon River. 1 RAR's role was to establish a blocking position in a village beside the river on the northern flank of the brigade's area of operations. In order to achieve tactical surprise, the operation was launched immediately following Operation Marauder, with the Australians and Americans redeployed by air.
Prior to the assault, the 1 RAR Operations Officer, Major John Essex-Clarke, conducted an aerial reconnaissance of the proposed Landing Zone—known as LZ June—on 7 January. Observing a lack of ground foliage, he was concerned about the possibility of extensive Viet Cong defensive works close to the LZ, and with the support of Williamson the landing zone was subsequently switched to a less-exposed location. The original plan would have seen 1 RAR inserted directly on top of a heavily defended bunker system, and would have likely resulted in heavy casualties. Captain Alec MacGregor, the commander of the 3rd Field Troop, was of the opinion that the "decision almost certainly saved hundreds of Australian lives."
Insertion, 8 January 1966
Napalm
Napalm is a thickening/gelling agent generally mixed with gasoline or a similar fuel for use in an incendiary device, primarily as an anti-personnel weapon...
and airstrikes from B-52
B-52 Stratofortress
The Boeing B-52 Stratofortress is a long-range, subsonic, jet-powered strategic bomber operated by the United States Air Force since the 1950s. The B-52 was designed and built by Boeing, who have continued to provide maintainence and upgrades to the aircraft in service...
bombers which resulted in significant defoliation. Soon after the airmobile operation commenced with the first American units being inserted by helicopter to the north, west and south. The US 3rd Infantry Brigade—under the command of Colonel William Brodbeck—was subsequently inserted by helicopter and by road. The brigade headquarters and command element departed Di An in convoy and reached Trung Lap on the western boundary of the brigade's area of operations by midday. Concurrently, two battalions were inserted by helicopter to the south-west, one blocking the south side of the Ho Bo Woods while the other conducted a sweep. The Americans were in contact almost immediately, although the engagements were generally small scale, or involving snipers. Meanwhile the brigade's third battalion moved by road to Trung Lap and then moved on foot to its assigned search area.
In the north, 1 RAR was inserted into its new landing zone—LZ March—3 kilometres (1.9 mi) to the south-west. With B Company securing the site, the battalion moved on foot to the line of departure but not before they were mistakenly engaged by US helicopter gunships and artillery fire. However, after the Australians established communications, the shelling was halted and they began their advance. No sooner had the lead elements—D Company under the command of Major Ian Fisher—emerged into the cleared area that was originally to have been used as the battalion's LZ, when the forward platoon
Platoon
A platoon is a military unit typically composed of two to four sections or squads and containing 16 to 50 soldiers. Platoons are organized into a company, which typically consists of three, four or five platoons. A platoon is typically the smallest military unit led by a commissioned officer—the...
came under fire from Viet Cong positions in the tree-line on the north-east corner. In the action which followed, six Australians from 12 Platoon were wounded, including platoon commander Lieutenant Jim Bourke, who was shot through the jaw but remained in command until he passed out from loss of blood. Meanwhile two medics who attempted to move forward to treat the casualties were themselves shot and killed.
Preece moved to push his other companies around each flank of D Company, and towards the battalion's original blocking position. Soon they were also in contact with small groups of Viet Cong from positions behind trees and in bunkers, while others popped up from spider holes and tunnel entrances; it became apparent to the Australians that they had stumbled across a significant Viet Cong force in extensive fortifications, sufficient to hold a battalion. B Company, under the command of Major Ian McFarlane, also uncovered a small dug-in hospital with simple transfusion equipment, documents and bandages. Meanwhile, the remaining battalions of the US 173rd Airborne Brigade had also been inserted. The 1st Battalion, 503rd Infantry Regiment flew into LZ April at 12:00, while 2/503rd Battalion arrived at LZ May at 14:30. With the insertion going largely according to plan, the brigades began their advance eastwards. Converging on the suspected location of the communist headquarters, a thorough search of the area yielded little, and it was believed that the Viet Cong had withdrawn earlier in response to the initial Australian advance.
Amid strong resistance, the Australians were made to fight their way through the maze of bunkers, punji stakes
Punji stick
The Punji stick or Punji stake is a type of booby trapped stake. It is a simple spike, made out of wood or bamboo, generally placed upright in the ground. Punji sticks are usually deployed in substantial numbers....
and booby traps but they were eventually able to force a Viet Cong regional force company to withdraw as they continued their advance. The area was heavily seeded with trip wires connected to shells and grenades dangling from branches, one of which blew McFarlane and several of his men off their feet. The defenders subsequently withdrew, with 7th Cu Chi Battalion forced north and 3rd Quyet Thang Battalion to the east. Suspecting they were being drawn into a trap—as one of the American battalions of the brigade had been previously during Operation Hump
Operation Hump
Operation Hump was a search and destroy operation initiated on 8 November 1965 by the 173rd Airborne Brigade, in an area about 17.5 miles north of Bien Hoa. The 1st Battalion, Royal Australian Regiment, deployed south of the Dong Nai River while the 1st Battalion, 503rd Infantry, conducted a...
—the Australians moved into a tightly defended perimeter before dark and waited for the communists to counter-attack. As night fell, movement was detected along a trench on the C Company perimeter when a squad of Viet Cong attempted to infiltrate the Australian position. Initially believing the movement to be another Australian patrol that had just departed on a clearing patrol, the machine-gunner on sentry duty finally opened fire at the last safe moment, killing one of the infiltrators at point-blank range and wounding a number of others before they withdrew.
Minor actions continued into the night, with small groups of Viet Cong able to pop up undetected and then disappear at will from within the Australian defensive position. The searching units were unable to locate Viet Cong in large numbers but experienced a significant number of sudden engagements and ambushes throughout the day, and it became clear that the communists were using tunnels for movement and concealment. Preece suspected that the area was honeycombed with tunnels and that the communist headquarters that he had been tasked to destroy was in fact located beneath the feet of the battalion. The Australians were the only battalion in the US 173rd Brigade to strike significant resistance, and by the end of the first day 1 RAR had suffered a total of three killed and 15 wounded, while the artillery Forward Observer from 105 Field Battery had also been killed. The battalion spent a sleepless night and in the early hours of the morning there were a number of short exchanges of fire as small groups of Viet Cong returned to the area. Not wanting to fire the machine-guns for fear of giving their positions away or hitting friendly troops, the Australians resorted to using grenades forward of the perimeter. Meanwhile, in the US 3rd Infantry Brigade area of operations contact had been light, with only six Viet Cong killed.
Tunnels of Cu Chi, 9 January 1966
The process of breaking into and exploring the communist tunnels began on 9 January, with the objective now switching to the location, clearance and destruction of the tunnel complexes. Whereas standard US Army practice was to seal, blow up or otherwise attempt to render tunnel systems unusable with smoke, tear gas and explosives before quickly moving on, the Australians spent the next few days laboriously searching and mapping the complexes they found using military engineers. Led by Captain Sandy MacGregor, the Australian sappers from 3 Field Troop systematically tackled the tunnels, using telephone line and compasses to plot the subterranean passages. Small-scale contacts between the communists and the Australians continued and MacGregor was later awarded the Military CrossMilitary Cross
The Military Cross is the third-level military decoration awarded to officers and other ranks of the British Armed Forces; and formerly also to officers of other Commonwealth countries....
for his leadership.
Originally constructed in 1945 by the Viet Minh
Viet Minh
Việt Minh was a national independence coalition formed at Pac Bo on May 19, 1941. The Việt Minh initially formed to seek independence for Vietnam from the French Empire. When the Japanese occupation began, the Việt Minh opposed Japan with support from the United States and the Republic of China...
during the fighting with the French in the First Indochina War
First Indochina War
The First Indochina War was fought in French Indochina from December 19, 1946, until August 1, 1954, between the French Union's French Far East...
, the tunnels at Cu Chi had taken decades to build but later had lain dormant after the war until 1960, when they were reactivated. Since then they had endured constant bombing, all the while being expanded. By 1965 they formed an underground maze of passages, fighting tunnels, meeting rooms and food caches, stretching from Saigon to the Cambodian border. Given their headquarters function, the tunnels were equipped with an array of communications and medical facilities and were defended by interlocking arcs of fire
Crossfire
A crossfire is a military term for the siting of weapons so that their arcs of fire overlap. This tactic came to prominence in World War I....
and connecting fire tunnels. Dug into hard clay which had largely protected them from American bombing, some trenches were reported as being more 1.8 metres (5.9 ft) deep, and some tunnels as long as 460 metres (503.1 yd), while numerous side tunnels led from the main tunnels. In places the system was between one, two and even three levels deep. The network was so extensive that they were rumoured to be able to hold 5,000 men, many of whom lived underground for up to six months at a time. On seeing the tunnels one American soldier described them at the time as "the New York subway".
In the southern area of operations, the US 3rd Infantry Brigade was making slow progress, with the Viet Cong using hit-and-run
Hit-and-run tactics
Hit-and-run tactics is a tactical doctrine where the purpose of the combat involved is not to seize control of territory, but to inflict damage on a target and immediately exit the area to avoid the enemy's defense and/or retaliation.-History:...
and ambush
Ambush
An ambush is a long-established military tactic, in which the aggressors take advantage of concealment and the element of surprise to attack an unsuspecting enemy from concealed positions, such as among dense underbrush or behind hilltops...
tactics to inflict casualties on the Americans, before withdrawing into the sanctuary of their underground tunnels. On 9 January, the Americans located and destroyed a cache of medical supplies, as well as a large amount of rice and a small hospital, as well as capturing 30 Viet Cong during a series of skirmishes. To the north, while 1 RAR searched the tunnel complex the American battalions of the US 173rd Airborne Brigade continued to sweep their area of operations, with a number of friendly fire
Friendly fire
Friendly fire is inadvertent firing towards one's own or otherwise friendly forces while attempting to engage enemy forces, particularly where this results in injury or death. A death resulting from a negligent discharge is not considered friendly fire...
incidents complicating their task. Both the 1/503rd and 2/503rd Battalions searched eastward toward the Saigon River and, although they continued to find supply caches and abandoned positions, they were involved in only minor skirmishes with the Viet Cong. Concealed in well-camouflaged ambush positions however, the communists inflicted a number of casualties on the Americans. Only one Viet Cong was killed during the fighting, bringing the total for the operation to just 22. Despite the large number of US troops involved they had experienced only limited contact to that point, and criticism of the operation consequently began to mount in the American media.
Fighting intensifies, 10–11 January 1966
The Australians continued to explore the tunnels, finding a large quantity of documents and equipment, and by 10 January they had recovered 59 weapons, 20,000 rounds of ammunition, 100 fragmentation grenades, one 57 mm recoilless rifle, explosives, clothing and medical supplies. At least 11 Viet Cong had also been killed in the fighting. Contact also continued, and overnight the Australians killed another five Viet Cong outside their perimeter, while numerous actions occurred during the day as the US 173rd Brigade maintained its sweep. On 10 January at 09:00 the American cavalry from Troop E, 17th Cavalry Regiment17th Cavalry Regiment (United States)
The 17th Cavalry is a historical organization within the United States Army that began as a regiment of cavalry after the Pancho Villa Expedition. The unit was constituted on 1 July 1916 in the Regular Army as the 17th Cavalry at Fort Bliss, Texas and originally inactivated 26 September 1921 at the...
and the Australians from the Prince of Wales Light Horse commenced a combined search operation and fought communist snipers and small groups throughout most of the day. At 14:00 a number of Viet Cong dug-in in trenches were encountered, and following a series of air-strikes and artillery barrages, the cavalry and the Australian M113s swept the area during which several Australians were slightly injured by a misdirected US Navy air-strike. Sixteen Viet Cong bodies were subsequently recovered, and another 60 were believed to have been killed but had been removed from the battlefield.
Williamson subsequently ordered the 1/503rd Battalion—under the command of Lieutenant Colonel John Tyler—to change the direction of its advance. During the morning the battalion had conducted platoon-sized patrols south, south-west and west, locating a well-constructed defensive position, including bunkers and trenches connected by tunnels. With no contact as yet made with the Viet Cong, the battalion prepared to move to a new AO in the north by 13:30. During this move the battalion, and armour from Troop D, 16th Cavalry Regiment
16th Cavalry Regiment (United States)
The 16th Cavalry Regiment is a Regiment of the United States Army first established in 1916.-Lineage:Constituted 1 July 1916 in the Regular Army as the 16th Cavalry and organized at Fort Sam Houston, Texas...
, engaged a dug-in Viet Cong Main Force company less than 2000 metres (2,187.2 yd) west of the Australians. Following air-strikes and heavy artillery bombardment the communists withdrew, leaving 29 dead during a sharp engagement. The 2/503rd Battalion had also sent out a number of squad-sized patrols during the day, but no recent signs of Viet Cong activity were found, and only minor sniper fire encountered. However, like the Australians, the American paratroopers also uncovered a large number of tunnels and other fortifications.
Meanwhile, the US 3rd Brigade continued to make slow progress and, despite reaching the banks of the Saigon River by 10 January, only a few brief glimpses of the Viet Cong had been made. A small base camp was discovered and destroyed however, while another battalion captured more than 10 tons of rice and 15 bales of cotton
Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective capsule, around the seeds of cotton plants of the genus Gossypium. The fiber is almost pure cellulose. The botanical purpose of cotton fiber is to aid in seed dispersal....
. The following day the Americans found and destroyed more bunkers and a number of houses and sampans, as well as quantities of supplies and food. They also uncovered a tunnel complex and a quantity of maps, charts and documents, although still little resistance was met. During these actions the Americans lost more men to booby traps than enemy fire. Advancing on a 1500 metres (1,640.4 yd) front, troops from the 1/28th Battalion—commanded by Lieutenant Colonel Robert Haldane—took a number of casualties from snipers, although the source of the fire was not immediately obvious. The Viet Cong attempted to avoid a set piece battle, opting instead to disperse into small groups to fight from their spider-holes and tunnels and only choosing to engage the Americans at close range with small arms, which included old Russian K-44 rifles. Despite suffering a number of casualties the Americans continued to advance, calling in artillery fire. Such tactics proved largely ineffectively though and the Commanding Officer of 2/28th Battalion, Lieutenant Colonel George Eyster, was himself shot and killed by a sniper during the fighting. Regardless, after receiving word of the discovery of the tunnels by US 173rd Airborne Brigade to their north, the brigade began another sweep.
The US 3rd Brigade subsequently also uncovered a significant tunnel complex, after Sergeant Stewart Green from 1/28th Battalion accidentally sat down on a nail and uncovered a trap door on 11 January. Volunteering to enter the tunnel, Green then located an underground dispensary occupied by more than 30 Viet Cong who subsequently escaped. Later a smoke machine was used to pump smoke into the tunnel system, and this was successful in locating numerous tunnel entrances and bunkers as the smoke rose above the jungle canopy. They were the first American troops to enter the tunnels, and they proceeded to attack them with CS gas
CS gas
2-chlorobenzalmalononitrile is the defining component of a "tear gas" commonly referred to as CS gas, which is used as a riot control agent...
, and later explosives. However, such tactics met with limited success with the tear gas flushing out large numbers of women and children, but few Viet Cong. Led by Green, a squad of Americans equipped with flashlights, pistols and a field telephone penetrated over 1.6 kilometre (0.994196378639691 mi) of the tunnel system before becoming involved in a fire-fight with the Viet Cong. Wearing gas-masks the Americans threw gas grenades and fought their way back to the tunnel entrance, but one soldier became lost in the darkness and Green re-entered the tunnel to find him. The Viet Cong subsequently withdrew.
Yet even as the Americans were attempting to clear the tunnels, heavy hand-to-hand fighting broke out above ground and Haldane was later awarded the Silver Star
Silver Star
The Silver Star is the third-highest combat military decoration that can be awarded to a member of any branch of the United States armed forces for valor in the face of the enemy....
for his actions when he rushed a bunker while under fire armed only with a pistol
Pistol
When distinguished as a subset of handguns, a pistol is a handgun with a chamber that is integral with the barrel, as opposed to a revolver, wherein the chamber is separate from the barrel as a revolving cylinder. Typically, pistols have an effective range of about 100 feet.-History:The pistol...
, in order to give first aid to a number of wounded soldiers. His courage inspired his men to complete the assault, and ultimately helped ensure the successful evacuation of the casualties and the capture of their objective. That evening the battalions of US 3rd Infantry Brigade had completed searching their assigned area of operation, and the following morning they were withdrawn from the operation. The brigade's involvement in Crimp had been limited, losing six killed and 45 wounded, while 22 Viet Cong had been killed. It was subsequently redeployed on Operation Buckskin.
Crimp continues, 12–13 January 1966
As they had done previously, the communists continued to attempt to infiltrate the 1 RAR perimeter during the night, and a minor clash with an Australian standing patrol occurred at dawn. Over the next two days, operations to exploit the tunnels continued, with the US 173rd Brigade and the Australians involved in a number of contacts, as well as suffering from sporadic sniper and mortar fire. Significant quantities of documents, equipment and rice were captured however, and large numbers of civilians detained for questioning. On 12 January, 1 RAR continued its patrolling program and one patrol subsequently located 15 tons of rice and destroyed it after killing six Viet Cong during a 20-minute battle. The task was complicated by the presence of a large number of civilians however, and many were found hiding in shelters and tunnels and they had to be coaxed out of hiding by the Australians and transported to a refugee camp which had been established nearby. Another patrol from 11 Platoon later uncovered a tunnel system just 50 metres (54.7 yd) from their position, and found it to be occupied by a large Viet Cong force after a dog and its handler were sent into the tunnel to investigate. Eight Viet Cong were subsequently killed after the tunnel was destroyed by Australian engineers.The same day, however, the Australian efforts to clear the tunnels had suffered a setback after an engineer became stuck in a trap door between one underground gallery and another, more than 2 metres (6.6 ft) below the surface. Despite the efforts of his comrades, he could not be recovered and died from asphyxiation after being overcome by a combination of tear gas, carbon monoxide, and lack of oxygen when he dislodged his respirator during the struggle to free himself. After days of living in close proximity to the enemy, the constant strain of sniper fire and the pressure of searching the tunnels was also beginning to take its toll, and a number of Australians were killed and wounded in otherwise avoidable friendly fire incidents on the evenings of 10 and 12 January. During the early afternoon of 12 January the Australians encountered a large group of armed Viet Cong during a tunnel clearance and called on them to surrender. However they failed to emerge and the tunnel was subsequently demolished, probably killing eight Viet Cong who were believed to have been entombed as it collapsed.
Meanwhile the same day Haldane ordered 1/28th Battalion to closely explore the tunnels in their area of operations, uncovering a number chambers and trapdoors defended by grenades and booby traps. A Company subsequently located another tunnel system after an American was killed by a Viet Cong soldier who suddenly appeared out of a large anthill. Later, as the 1/503rd continued to search its area with platoon-size patrols during the afternoon of 13 January, a clash between Company C and a Viet Cong platoon developed into a heavy contact. An air-strike was successfully called in by the Americans however, and a search of the area recovered 10 dead Viet Cong, while blood trails and human remains indicated that perhaps another 20 were also killed.
Action concludes, 14 January 1966
Ultimately, more than 17 kilometres (10.6 mi) of tunnels had been uncovered and searched by the Australians. A large quantity of documents had been recovered, including more than 100,000 pages detailing operational structure as well as the names of agents operating in Saigon. Ninety weapons were also captured, as well as thousands of rounds of ammunition and enough equipment, food and other supplies to fill eight 2½-tonne trucks. Although the US battalions had played a large part in the operation and had also uncovered numerous tunnel systems and been involved in heavy contact, by the fortunes of war 1 RAR had been allocated the area of operations that was ultimately found to contain the Viet Cong headquarters. The Australians had even partially searched the tunnel leading to the headquarters that was their objective, but did not learn how close they had come to succeeding until decades after the war had ended. During the course of these activities the searchers had suffered a number of additional fatalities from Viet Cong snipers.Fully exploring and destroying the tunnels was well beyond the allied resources available, and the decision was eventually made to call a halt to operations. Six days after it began, Operation Crimp ended, with 1 RAR returning to Bien Hoa on 14 January. By the time the operation was concluded only a fraction of the known tunnel network had been destroyed and it was not until after the war that it was learnt that the system at Cu Chi actually included more than 200 kilometres (124.3 mi) of tunnels. Although further American ground operations as well a number of heavy B52 bombing raids resulted in further damage to the tunnel complexes, the Ho Bo Woods were never occupied on a permanent basis and the Viet Cong were successful in restoring their transit and supply functions. As such, despite significant disruption, the military and political apparatus in Cu Chi remained largely intact, allowing the communists freedom of action for later operations against Saigon.
Aftermath
During the fighting the Australians had faced stiff resistance and had suffered eight killed and 29 wounded, while claiming 27 Viet Cong killed and a further 30 probably killed. The Americans had also been involved in heavy fighting and their casualties included 14 killed and 76 wounded. Total communist casualties included 128 confirmed killed, and another 190 probably killed, as well as 92 captured and another 509 suspects detained. In addition many more Viet Cong were thought likely to have perished in the tunnels as they were collapsed by charges laid by the Australian engineers. The Americans later claimed that the headquarters of the communist 4th Military Region had also been destroyed. Due to the quantity of information recovered from the thousands of captured documents alone, the battle was later described as the first allied strategic intelligence victory of the war. So significant was the find that both Westmoreland and General Joseph McChristianJoseph A. McChristian
Joseph A. McChristian was a US Army Brigadier General and the Assistant Chief of Staff for Intelligence, Military Assistance Command, Vietnam from July 13, 1965 to June 1, 1967....
, the head of Intelligence at MACV
Military Assistance Command, Vietnam
The U.S. Military Assistance Command, Vietnam, MACV, , was the United States' unified command structure for all of its military forces in South Vietnam during the Vietnam War.-History:...
, visited 1 RAR during Operation Crimp.Neither Westmoreland nor McChristian referred to the operation in their end of tour reports, however. See McAulay 2007, p. 34. Allied operations against the communist tunnels had been largely ad hoc, and the Australians began to develop the earliest techniques for exploring and destroying them. Later, at least partially as a result of the success of the Australians in clearing some of the shorter tunnels, American units adopted similar tactics and created a number of tunnel-clearance teams, known popularly as Tunnel Rats.The Australian teams were originally referred to as "ferrets". See Mangold and Penycate 1985, p. 56.
Despite the losses suffered by the communists, the combined American and Australian force had only succeeded in partially clearing the area and the tunnel network it concealed, and consequently the Ho Bo Woods would remain a key communist transit and supply base throughout the war. Indeed the bulk of the communist force had successfully withdrawn intact, leaving only rear guard elements in defence, prompting the communists to also declared the operation a victory, claiming almost 2,000 American troops killed or wounded, 100 vehicles destroyed, and 50 aircraft shot down. Yet, such claims were based on estimates of casualties caused by command-detonated mines, punji sticks and other booby traps, and proved to be wildly inaccurate. In fact Operation Crimp had rattled the communists, and they subsequently ordered their units in the south to prevent the Americans from concentrating their forces in the future. Regardless it also highlighted the inherent weakness of the search-and-clear operations that would later become standard operating procedure for the US Army in Vietnam.
At the strategic level, the allied enclave strategy proved only transitory. Further setbacks led to additional troop increases to halt the losing trend, with US troop levels planned to rise from 210,000 in January to 326,000 by December 1966. In March 1966, as part of this strategy, the Australian government also increased its commitment to the ground war in Vietnam, committing a two battalion brigade—known as the 1st Australian Task Force
1st Australian Task Force
The 1st Australian Task Force commanded the Australian and New Zealand Army units deployed to South Vietnam between 1966 and 1972. 1 ATF was based at Nui Dat in Phuoc Tuy Province...
(1 ATF)—with armour, aviation and artillery support; in total 6,300 personnel. 1 RAR was subsequently replaced and 1 ATF was allocated its own area of operations in Phuoc Tuy Province
Phuoc Tuy Province
Phước Tuy Province was a province of South Vietnam. It now mostly corresponds to Ba Ria-Vung Tau Province, just southeast of Ho Chi Minh City....
, thereby allowing the Australians to pursue operations more independently using their own tactics. The task force arrived between April and June 1966, constructing a base at Nui Dat
Nui Dat
Nui Dat in Phuoc Tuy Province was the location of a prominent Australian military base in South Vietnam during the Vietnam War. The site was chosen by Lieutenant General John Wilton in 1966 and was built mainly by men from the 6th Battalion, Royal Australian Regiment...
, while logistic arrangements were provided by 1st Australian Logistics Support Group
1st Australian Logistics Support Group
The 1st Australian Logistic Support Group was a ground support unit of the Australian Army during the Vietnam War located at Vũng Tàu. The unit was formed in 1965 as the Australian Logistic Support Company and was redesignated as 1 ALSG in April 1966.1 ALSG commanded logistic support units to all...
which was subsequently established at the port of Vung Tau
Vung Tàu
Vũng Tàu is a city in southern Vietnam. Its population in 2005 was 240,000. The city area is including 13 urban wards and one village. It is the capital of Ba Ria-Vung Tau province, and is the crude oil extraction center of Vietnam. It is also known as one of the most beautiful cities of tourism...
. Operation Crimp was 1 RAR's third and last foray into the communist heartland and following the fighting they had more than two weeks rest in Bien Hoa—their longest break from operations during the battalion's tour. However, further operations followed in the months afterwards, including the Battle of Suoi Bong Trang
Battle of Suoi Bong Trang
The Battle of Suoi Bong Trang was a major action during the Vietnam War fought between US and Australian troops, and the Viet Cong and North Vietnamese Army...
on the night of 23–24 February 1966.
The Ho Bo Woods were again targeted by the Americans in January 1967, during a much larger operation known as Operation Cedar Falls
Operation Cedar Falls
Operation Cedar Falls was a military operation of the Vietnam War conducted primarily by US forces. The aim of this massive search and destroy operation was to eradicate the so-called "Iron Triangle", an area located in close proximity to Saigon which had become a major stronghold of the communist...
. However despite heavy casualties again being inflicted on the Viet Cong, the tunnels continued to remain a problem for the Americans and they were later used as a communist staging area for the attack on Saigon during the 1968 Tet offensive. Finally in 1970, American B-52 bombers carried out a number of heavy air-strikes on the area, dropping thousands of delayed-fuse bombs that buried deep into the ground before exploding, ending the tunnels' utility.