At 4.00 a.m. on the morning of 25 June 1950 North Korean armed forces launched a devastating attack on South Korea and within hours had crossed the 38th Parallel. This began the Korean War, which lasted over two years until a final cease-fire on 27 July 1953. It has been the only conflict since 1945 in which the armies of two great powers—the United States and China—met on the battlefield. The Korean War transformed relations between the United States, the Soviet Union and China in Asia and froze them into a cold war mould for the next two decades.
The Korean peninsula itself occupied a sensitive, strategic point bridging China and Japan; but in 1950 it was an obscure, politically divided, economic backwater from which both the United States and the Soviet Union had withdrawn their occupying forces in the previous year. In order to understand why the Korean War played such a crucial role in shaping East-West relations, it is necessary to examine two related events: the triumph of communism in China in 1949; and the United States’ attempt to apply the policy of containment to Asia.
In 1911 the Chinese nationalists, led by Sun Yat Sen, overthrew the Manchu dynasty and set up a republic. Thereafter, China