The spectacular defeat and surrender of the British forces at Singapore and the subsequent threat to the Australian mainland exposed a weakness in the British empire's defenses in World War II. And it came as something of a profound shock to Australia when Britain announced in 1942 that Australia must look out for itself, since the "land down under" was too far away from the mainland U.K. for assistance to be sent.

Disaster was only averted by the strong defense mounted by the United States. Gradually, Australia's citizens came to feel that their country was tied more closely to the United States than to the mother country halfway across the globe. Naturally the ties of blood, family and culture would never be severed, but the emphasis was irrevocably altered by WWII. When communism began haunting the political leaders of the west, both the Australian and New Zealand governments were swift to support the United States both politically and militarily. In Korea in 1950 they made strong contributions to what would become a Commonwealth division of British, Canadian and other former Empire nations.

The role of mechanized forces, and particularly the tank, was the subject of much debate within the Australian armed forces. Developments during World War II had resulted in the basic concept of a large main battle type tank, armed with a heavy gun and intended for operations in central Europe against an armored opponent. For some 30 years after WWII ended, politicians and senior military officers questioned the need for Royal Australian Armoured Corps (RAAC) tanks and armored personnel carriers (APCs) in what was a small, infantry-oriented army. In the Korean War, the RAAC served with British armor. Its contribution there served to justify its continued existence, at least for a while.

The Malayan emergency and other threats to Indonesia and Vietnam led to the formation of the Southeast Asia Treaty Organisation (SEATO) in September 1954. Australia and New Zealand were signatories to that compact, which aimed to check the growth of communism throughout the region. In April 1956, when the French finally departed from South Vietnam to be replaced by an American military training group, Communist military activity increased throughout the region. In due course, with the scale of American involvement steadily increasing, it became inevitable that Australia and New Zealand would be drawn into the conflict. As early as 1962, the Australian government of Robert Menzies sent 30 advisers to Vietnam to support the U.S. Special Forces with their ill-fated Strategic Hamlet scheme, as well as the general training of ARVN regular and militia units. Within three years, the number of advisers had risen to more than 100. Many were Special Air Service personnel with experience in Malaya, where the British had defeated Communist insurgents, and in Borneo, where confrontation was in progress against Indonesian forces.

After the first U.S. Marine combat units landed at Da Nang on March 9, 1965, plans were swiftly developed for their reinforcement by another 82,000 men. America's Pacific allies pledged a further 7,250, including an ANZAC (Australia-New Zealand Army Corps, named for the formation originally created for the Gallipoli operation of World War I) battalion to support the new enclave strategy. This initially consisted of the 1st Battalion, Royal Australian Regiment (RAR), with the 105th Battery, Royal Australian Artillery, in addition to logistics, medical engineering personnel and a small armored contingent. This included eight M113 APCs from A Squadron, the 4/19th Prince of Wales' Light Horse, inevitably nicknamed "the Ponies" by the diggers, or ordinary soldiers, which arrived in June. Many in the military hierarchy did not understand why armor was being sent on a counterrevolutionary mission, and some actively sought to prevent it. The following month the 161st Battery, Royal New Zealand Artillery, arrived in Vietnam and was integrated into the Australian organization.

The ANZAC battalion was not considered strong enough initially to operate on its own in Vietnam. For the first year, the fledgling ANZAC force operated closely with the 173rd Airborne Brigade based at Bien Hoa, proving extremely effective in search-and-destroy operations around Saigon. At this stage, however, participation in the war was very unpopular down under. Further deployments were restricted to an increase in the complement of the 161st's Battery, Royal New Zealand Artillery, bringing the APC troop up to strength, 13 vehicles plus two M125A1 mortar carriers in September. In June 1966 the 1st Australian Task Force was created. Added to the 1st RAR were the 5th and 6th Battalions, supplemented by two companies from the Royal New Zealand Infantry Regiment and the 103rd Field Battery, while the APC detachment was expanded to a squadron. That unit eventually became A Squadron, 3rd Cavalry Regiment, in January 1967, supported by the 106th Field Workshop, Royal Australian Electrical and Mechanical Engineers. With the established of the task force, personnel of the 1st RAR were replaced in theater with members of the 7th Battalion.

In addition to the ground forces sent to Vietnam, the Royal Australian Air Force sent several squadrons. Number 9 Squadron, equipped with Bell UH-1B Iroquois helicopters, and Number 35 Squadron, equipped with Caribou transport planes, were based at Vung Tau in June 1966. Logistical backup and heavy artillery support were provided principally by the American forces, particularly transport helicopter operations. By October 1967, there were some 8,000 Australian and 550 New Zealand personnel deployed in Vietnam, including HMAS Sydney, a converted troop carrier­supply ship, and the destroyer HMAS Hobart.

The creation of a brigade-size grouping meant that the ANZACs could now take responsibility for their own area of operations. They were assigned the province of Phuoc Tuy, a coastal region southeast of Saigon. Rear echelon operations were established at Vung Tau, on the coast, but the Task Force headquarters and base of operations was at Nui Dat, more centrally located in the province. When they arrived, the ANZACs found that the region was a hot spot of VC activity. Measuring some 30 kilometers north to south and 60 kilometers east to west and divided by two principal roads, the region consisted largely of open paddy fields as well as villages, to provide the enemy with recruits and supplies. But there were also large areas of hills and jungle where VC could find shelter. In December 1964 the 9th VC Division had destroyed two battalions of ARVN troops at Binh Gia. Seven battalions of VC were operating in the province, and main force units had developed political cadres within and control over most of the villages in the area, with a series of jungle bases. The VC appeared to have already won the war in Phuoc Tuy province.

The ANZACs set to work, employing the aggressive patrolling, ambushes and logistic denial techniques learned in Malaya. In so doing, they effectively denied the VC freedom to operate and regenerate in the area. Of particular significance in the fight against the VC was the arrival in June 1966 of the 3rd Squadron, SAS. That unit had recently been employed in Borneo, where they had perfected the surveillance and information gathering skills so critical to counterrevolutionary warfare. At the time, the emphasis on recon as opposed to offensive operations was little understood by the task force commanders, who had their own ideas on the role suitable for the SAS. But by the end of 1967 the SAS men had established a formidable reputation thanks to their success in gathering information and harassing the enemy. The VC and NVA knew them either as the Biet Kich Ue Da Loi, the Australian Commandos, or Ma Rung, the Ghosts.

While working with the 173rd Airborne Brigade at the beginning of Australian involvement in Vietnam, members of the 1st RAR had been impressed with the direct fire support provided by the Americans' M48A3 Patton tank with its 90mm gun. When Pattons were unavailable, the infantry increasingly looked to the APCs, with their .5-inch Browning machine guns, to provide fire support. Virtually all tracked vehicles were retrofitted with the Cadillac Gage M47C turret (T50 after 1968), with twin .3-inch Brownings. Apart from their primary role of transporting the infantrymen to the battlefield, they were also used to tow artillery and trailered loads. In addition, they were employed for ammo resupply, removal of captured weapons and equipment and convoy escort. They were employed, as well, for ammo resupply, removal of captured weapons and equipment and convoy escort. Given the vehicles' aluminum hulls and the stuffy conditions inside, many infantrymen preferred to ride on top of the transports.

It was apparent by the close of 1967 that the M113s were unable to provide adequate support for the infantry, which was increasingly involved in missions better suited to light tanks. The M113s were very vulnerable to RPGs and heavy machine-gun fire. Consequently, it was decided to deploy elements of the 1st Armoured Regiment to Vietnam, equipped with the elderly British-built Mark 5 Centurion tank. Weighing around 50 tons and armed with a 20-pounder gun, the Centurion had proved itself in Korea and would soon do so again in Israeli service. It was being replaced in service by the British Army, and the Australians were considering replacing it as well. The tanks were known as Koalas because they were not to be exported and not to be shot at.

Despite the fact that there was apparently no need for the Koalas--expensive, relatively slow machines designed for mechanized warfare in western Europe--ANZAC authorities sent to Vietnam a squadron of two troops (a total of eight vehicles) plus two for a headquarters, two with bulldozer attachments, two bridge-layers and an armored recovery vehicle, plus three replacement tanks to offset attrition. Almost immediately, it seemed that their presence in-country was a mistake. Driving slowly through Vietnam's heavy undergrowth and regularly operating at very slow speeds caused enormous wear on running gear and drive trains, as well as reducing the tanks' engine life and increasing fuel consumption alarmingly. The three replacement tanks were soon cannibalized for spares, and further spares had to be flown in from Britain to keep the remaining tanks running.

All the tanks were taken to Nui Dat and reworked. Much of the trouble was apparently caused by vegetation accumulating behind the bazooka plate and beneath the track guard overhangs. Those devices were removed to provide extra armor for machine-gun shields for tanks and APCs--and also to construct barbeques, a welcome reminder of home for the ANZAC troops, who frequently socialized between missions over the "barbie." Additional fuel tanks and extra machine-guns were added, and the Centurions were able to continue operating in Vietnam at 75 percent availability. They were able to negotiate all of Phuoc Tuy province during the dry season and most of it during the wet, but there were still some "no go" areas, as there were with the APCs.

By the time of the 1968 Tet Offensive, the province was under allied control. By late February 1968, intelligence suggested that the NVA would attempt to follow up the offensives in South Vietnam to try and retrieve a vestige of success from the debacle. To counter that, a substantial part of the 1st Australian Task Force, including the two troops of Centurion tanks, were sent to Bien Hoa province, northeast of Saigon, to establish fire support bases Coral and Balmoral in the enemy's anticipated path. Between May 12 and June 6 the 1st and 3rd RAR, supported by APCs and the tanks of C Squadron and practically unlimited American air support, held off attacks by no fewer than three NVA regiments that were attempting to infiltrate the huge American logistics base at Long Binh and Saigon, in what was the biggest single action fought by the ANZACs during the war.

After a couple of weeks, the NVA forces gave up any serious attempts to infiltrate into Saigon and were desperate to withdraw northward. On May 30, after being engaged primarily against the 141st and 165th regiments of the NVA's 7th Division, C Company, the 1st RAR under Major Ian Campbell moved out from FSB Coral to clear an area of dense jungle believed to be concealing the divisional headquarters of the mauled 7th Division. Campbell had requested the support of four Centurions operating out of Coral, but all four were under maintenance following search-and-destroy patrols carried out by other units in the two firebases. Consequently, C Company set out alone, transported in APCs to the edge of the jungle and then going forward on foot.

At 0900 hours, the lead platoon clashed with a three-man NVA recon detachment that hastily retired. The 9th Platoon pursued them, followed by the rest of the company, but they were soon under heavy small-arms fire from concealed bunkers to their front and pinned down. The 7th Platoon attempted to work around to the flank, but they, too, came under heavy fire from small arms and RPGs. The company had been effectively pinned down and as it began to come under heavy mortar fire.

Campbell realized that he was in trouble. They had walked into a complex of bunkers and were now surrounded. Artillery support was difficult to direct in the close bush and would be dangerous to his own men given the close proximity of the enemy. American Army helicopter gunships were similarly hindered from providing effective assistance. Maintenance or no maintenance, the tanks of the 1st Troop were desperately needed.

One of the vehicles was not in service at that point, and radio failure in a second resulted in an ad hoc force of two tanks and two other vehicles' being dispatched to the contact. No additional infantry were sent, but the APCs returned to the scene. When the tanks arrived, they found the M113s vainly trying to push through the dense undergrowth to retrieve C Company and boldly pushed past them. Once they reached the infantry's position, the tankers were hampered by the perennial problem of communications. Although both infantry and armor had radios, they were not always compatible. Often the two had to be linked by a third party, such as the artillery net, in order to provide a three-way link. However, it all took time.

The Centurions encountered the first wounded diggers barely 40 meters into the bush. Given the difficulties of communications and the density of the bush, there was a grave danger of running over their own men. At the same time, they were already taking small-arms fire. Slowing to a crawl to gingerly pick their way through the prone and crouching infantry, the following APCs were able to extract their wounded mates. Since the armored troops were unwilling to open their hatches because of the volume of fire at very short range, communications were established slowly. Eventually, Campbell was able to give the tanks clearance to fire. They cleared the vegetation and undergrowth off the bunkers using canister fire.

Commanding the 1st Troop was Gerry McCormack, who later recalled: "We then cleared the bunkers that were obvious and went forward, at which point a burst of machine-gun fire right alongside scared me, and I asked Reeves to cover the front while I found out what the hell was going on. At first I thought it was our infantry firing, but over the radio I was told it wasn't, it was an enemy right about where I was. I asked the infantry if they could see where it was coming from, and they said 'You are sitting on it.' We'd been so careful about getting forward of our infantry casualties that we'd actually straddled an enemy pit, and when we moved sideways to deal with the fellows who came running with an RPG, we released part of the entrance to their bunker. We couldn't reverse off because we still had the casualties behind us. I picked two hand grenades out of the inside of the turret and, by a bit of judicious poking my head over, found out where the devil he was, then positioned the tank so I could just drop them over the side. They went into the pit, and that silenced the machine gun."

Having orientated themselves, the Centurion crews approached each bunker in turn, depressed the gun barrel and fired high explosive at point-blank range. Eight bunkers were eliminated in turn in front of the 7th Platoon, but the NVA continued to maneuver around the Australians and showed no signs of breaking off contact. By 1030 Campbell realized that, even with the tank support, the bunker complex was much too extensive for his single company and two tanks to account for. He decided to withdraw 500 meters and call in an airstrike. As they withdrew, the battle did not slacken in intensity. Amid a deafening roar of small-arms and 20-pounder fire, and covered by a thick cordite mist that clung to the floor of the jungle, an RPG team hit the M113 evacuating the wounded. By great good fortune, it hit some water jerrycans strapped to the outside of the armored vehicle, and the round detonated prematurely. There was such a volume of small-arms fire aimed at the tanks, however, that the external fittings were literally being shot away.

Eventually the tank movements created clear enough fields of view for the Huey gunships waiting overhead to distinguish the Aussies from the NVA, and they poured a withering fire onto the enemy. Farther up, McDonnell Phantoms were awaiting the call to attack. Behind the tanks, the Aussies were trying to reach the relative safety of the APCs while the NVA were doing their best to keep them from doing so. Canister rounds fired at close range stopped the NVA infiltration groups. Knowing there would be a napalm and high explosive inferno after contact broke off, the NVA tried desperately to keep up the assault. By 1100, the APCs were disengaging with their cargoes of weary diggers and laying down covering fire on the flanks as they moved away from the fight. After their bunker-busting sweep, the Centurions reversed slowly out, continuing to lay down canister and machine-gun fire onto the position and to their flanks to deter enfilade fire and movement.

Back in the open, they quickly resupplied with ammunition. They had both expended most of their 60 rounds of main armament ammunition. Both Campbell and McCormack favored re-forming with fresh elements of the 1st RAR and re-entering the bunker complex in order to finish the job. The 1st ATF Headquarters at Nui Dat vetoed this plan, however, in favor of bringing in the circling Phantoms. Campbell believed that the tanks had saved the day. The Australians lost one dead and seven wounded in the skirmish, but those casualties had all been sustained prior to the Centurions' arrival. The firepower they had provided had not only broken up attempted counterattacks by the NVA forces but had facilitated the relatively easy evacuation of the casualties by the APCs, which could not have otherwise reached the scene and were vulnerable once there.

On many similar occasions the tanks proved their value, but they often performed mundane and unglamorous tasks as well. One common role assigned to them was supporting "roadrunner" tasks performed by the APCs, keeping the vegetation back from the main convoy highways where ambushes might be concealed. This was achieved by tying a maritime anchor chain between two tanks, which then straddled the road, ripping up the vegetation with the dragged chain. The tanks also were used to destroy crops believed to be destined for the enemy.

The infantry came to love the Centurions. The contribution the tanks made during the battles in defense of Coral and Balmoral impressed everybody up to the 1st ATF Headquarters. The troop commanders found themselves inundated with requests for combined operations from infantry company commanders. They could advance in front of the infantry, detonating booby traps.

The NVA learned to fear the Centurions, since they lacked effective anti-tank weapons. The tanks were largely impervious to RPG rounds, but the standard Chinese Chi-com anti-tank mine could blow a suspension, roadwheel or track. However, the NVA would often retire to fight elsewhere rather than take on infantry supported by tanks. The tanks would sometimes act as the "hammer," sweeping the NVA toward prepared defensive positions, or "anvils." As a result, a third ad hoc troop was formed using the two headquarters tanks and the two bulldozer variants. The bridge-layers served in their own right and were also pressed into service as troop carriers. They even served as helicopter landing pads in areas of thick undergrowth. Such was the success of the Centurions that the 3rd and 4th troops, with a further eight tanks, were deployed in September 1968. The ad hoc 5th Troop also remained in Vietnam. A total of Centurions served in Vietnam before being withdrawn in September 1971.

Returning to Phuoc Tuy after the FSB Coral and Balmoral engagements, the 1st ATF found that VC were being replaced by fresh, well-fed NVA units infiltrating into South Vietnam. The ANZACs soldiered on in Phuoc Tuy until 1971, when they returned home as part of the general withdrawal of Allied forces. The last ANZAC unit left in early 1972.