A relatively new type of remotely-detonated mine, the explosively formed penetrator has been used with some success against American armoured vehicles. Some of them remain in use in the 21st century.Īs of 2005, there were 1,100 M1 Abrams used by the United States Army in the course of the Iraq War, and they have proven to have an unexpectedly high level of vulnerability to roadside bombs. These vehicles and their derivatives formed the bulk of the armored forces of NATO and the Warsaw Pact throughout the Cold War. The M47 series evolved through to the M60 series. The T-55 started with a 100 mm gun, but has been upgraded with both 105 mm and 125 mm guns, much improved fire control systems, new engines, track, etc. For example, the Centurion began life with the highly effective 17-pounder (76.2 mm) gun, but was upgraded to 20 pounder (84 mm) and then 105 mm main armament by 1959, with improved fire control and new engines. These three basic vehicles were upgraded significantly over time. The classic main battle tanks of the 1950s were the British Centurion, the Soviet T-55 series, and the US M47 and M48 series. Yet they were cheap enough to be built in large numbers. Typical Main Battle Tanks were as well armed as any other vehicle on the battlefield, highly mobile, and well armored. The Main Battle Tank thus took on the role the British had once called the 'Universal tank', filling almost all battlefield roles. Even reconnaissance vehicles had shown a trend towards heavier weight and greater firepower during World War II speed was not a substitute for armor and firepower. Likewise, World War II had shown that lightly-armed, lightly-armored tanks were of little value in most roles. The World War II concept of heavy tanks, armed with the most powerful guns and heaviest armor, became obsolete since they were just as vulnerable as other vehicles to the new medium tanks.

This transition happened gradually in the 1950s, as it was realized that medium tanks could carry guns (such as the US 90 mm, Soviet 100 mm, and especially the British L7 105 mm) that could penetrate any practical level of armor at long range. Medium tanks gradually evolved into the new concept of the MBT.

Medium modern tank