During the opening stages of the Korean War, M24s were the initial U.S. tanks directed to combat heavier and larger North Korean T-34-85s supplied by the Soviets. The occupation troops in Japan from which the Chaffee tanks were drawn were inexperienced and under-equipped due to rapid demobilization after World War II. One other reason for sending Chaffees to Korea initially was also partly because US officers did not regard Korea as a country where large-scale tank warfare could occur (much of the Korean peninsula is largely mountainous and hilly) and therefore sent lighter armored vehicles to combat the invading North Korean forces. The M24 fared poorly against the invading army's better-armed, better-armored and better-crewed medium tanks, losing most of their number while inflicting only minor damage on the T-34 tank units. Managing a fighting withdrawal, they ended up as infantry-support artillery in the Pusan Perimeter, and in August reinforcements from the US and the Commonwealth brought heavier tanks that were a match for the T-34s, not to mention superior infantry anti-tank armaments and overwhelming air support against North Korean armor. M24s were more successful later in the war in their reconnaissance role and supported by heavier and more capable tanks such as the M4 Sherman, M26 Pershing and M46 Patton, along with British Churchill, Comet and Centurion tanks.