Tanks in the Cold War Korean War M24 Chaffee's were the first U.S. tanks to fight the North Korean T-34-85s. The Chaffee fared poorly against these much better-armed and armored medium tanks. Chaffees were more successful later in the war in their reconnaissance role, supported by heavier tanks such as the M4 Sherman, M26 Pershing, and M46 Patton. The heavier but older Pershing was deemed unsatisfactory due to its inferior mobility, which was unsuitable for a medium tank role as it used the same engine that powered the much lighter M4 Sherman, and 1949, the upgraded M26 received a new power plant and a main
M4 Sherman combat service in many conflicts around the world, including the UN forces in the Korean War, with Israel in the Arab–Israeli wars, briefly with South Vietnam in the Vietnam War, and on both sides of the Indo-Pakistani War of 1965. The U.S. Army Ordnance Department designed the M4 medium tank as a replacement for the M3 medium tank. The M3 was an up-gunned development of the M2 Medium Tank of 1939, in turn derived from the M2 light tank of 1935. The M3 was developed as a stopgap measure until a new turret mounting a 75 mm gun could be