Although the U.S. sent armor advisors to South Vietnam to help them establish their own armored force, the U.S. Army did not see a real role for American armor in that war prior to 1965. However, experiments with armored cavalry in Germany had demonstrated its potential area security role against saboteurs, guerillas and airborne attack. That led to the development of some basic concepts on how to use an armored cavalry regiment in a counter-insurgency (COIN) role.
As the large-scale U.S. ground build-up got under way in Vietnam, debate continued on whether its jungles and rice paddies were appropriate terrain for armor or mechanized infantry. Indeed, the first tanks deployed there essentially were limited to perimeter guard duty around major fixed facilities.
“Two things ultimately overturned that policy – the experience of U.S. advisors with Soviet armor units in the early 1960s provided practical experience in how to use armor units in all areas of Vietnam, including jungles and rice paddies,” Cameron said. “Second, the units themselves and their commanders began to develop their own TTPs (tactics, techniques and procedures) on how to operate. What armor brought to Vietnam was the ability to move, engage just about any target and provide a great deal of armor protection.”
As U.S. armor began to encounter Viet Cong and North Vietnamese infantry, the enemy found the M48 hard to stop. Especially at the company level, U.S. forces began to find a variety of ways to employ armor, such as avoiding heavily booby-trapped jungle paths and using the tank’s bulk to batter out their own path, instead. And once contact was made, the M48 proved a major contributor to overwhelming or at least suppressing the enemy.
In the early 1970s, the U.S. and Germany began a program to replace the M60 with the MBT-70, which could operate in a nuclear-biological-chemical (NBC) contaminated environment. However, the program soon became overly expensive for the Germans, who pulled out in favor of new upgrades to their Leopard tank.
“No M60s deployed to Vietnam; all those remained in Central Europe for use against the Soviets,” Cameron said. “But M48s took a lot of hits and, even if one ran over a mine, the crew was likely to survive. So it was a powerful weapons platform used in many different environments, including rubber plantations, urban areas and during the Tet offensive. The gun also could fire a canister round, which created multiple bad days for threat personnel.”
When the first Sheridans arrived in Vietnam, their light weight and maneuverability were seen as major pluses, the canister round was a highly effective defoliant and the main gun’s conventional round proved to be an excellent bunker buster. But there also were negatives: The aluminum hull was vulnerable to mines and rockets, especially if hit in the magazine; the Sheridan’s combustible cartridge sometimes left smoldering debris in the tube, creating the potential for a catastrophic accident when the loader put a new round in the tube; the North Vietnamese soon became more adept at countering armor, placing a light system in even greater danger.
One complaint against the Sheridan had little import in Vietnam – firing the main gun tended to destabilize the Shillelagh missile control system. By the time the Sheridan arrived, there was not much of an armor threat remaining in Vietnam requiring the missile. However, that problem was a serious concern for the tank’s possible use in Europe.
The military came out of Vietnam believing there were few armor lessons to be learned from the experience that could be applied to what was still considered the real probable future battlefield – Central Europe.
In the early 1970s, the U.S. and Germany began a program to replace the M60 with the MBT-70, which could operate in a nuclear-biological-chemical (NBC) contaminated environment. However, the program soon became overly expensive for the Germans, who pulled out in favor of new upgrades to their Leopard tank. Congress agreed and the program died, leaving the U.S. Army with no future MBT program and forced to follow the German path with upgrades to the M60, which originally had been intended only as a temporary platform.