The decade after World War Two saw communism spreading to the Far East. While China became communist in 1949, it was the conflict in Korea that proved to be the biggest crisis for relations between the USA and the USSR in the 1950s.
The success of communism in China had persuaded the USA that their domino theory was correct. This suggested that if one country was allowed to fall to communism, then communism could quickly spread to neighbouring countries. In 1950 a report by the American National Security Council recommended that the policy of containment was not enough, and that what was needed was roll back, or action to regain territory from communist control.
What caused the Korean War?
After World War Two, Korea had been divided at the 38th parallel into the Soviet-backed communist North Korea, led by Kim Il Sung, and non-communist, American-backed South Korea under the leadership of Syngman Rhee.
In June 1950, with the support of China and the Soviet Union, North Korea launched an attack on South Korea across the 38th parallel.
America and the UN to the rescue
June 1950: the North Korean People’s Army advanced quickly and pushed the Southern forces to a small area around Pusan in South Korea.
July 1950: fearing a communist takeover, the USA sent troops to support South Korea.
July 1950: the USA appealed to the United Nations for help and its Security Council agreed to send troops. This request was only granted because the Soviet Union was boycotting the Security Council over the admittance of the Nationalist Chinese delegation to the United Nations. Had the Soviet Union been in attendance at the vote, they would have vetoed the request for support.
September 1950: UN forces, led by the American General Douglas MacArthur, landed in Inchon and quickly pushed the North Koreans back over the 38th parallel and by October 1950 they had almost rolled back the communists to the Yalu River on the border with China.
October 1950: not wanting a US-backed state on its border, China invaded Korea and drove the UN forces back below the 38th parallel. General MacArthur called for the use of atomic weapons to defend Korea but this was denied by President Truman and MacArthur was sacked.
June 1951: more UN troops were deployed to Korea and the communists were eventually driven back to the 38th parallel. The war became a stalemate.
November 1952: Republican, General Dwight D Eisenhower won the US presidential election, promising he would go to Korea to see how the war could be ended.
July 1953: an armistice was signed at Panmunjom on the 38th parallel, which left Korea divided as it had been in 1950, and still is today.
Impact and consequences of the Korean War
The Korean War was an important development in the Cold War because it was the first time the two superpowers, the United States and the Soviet Union, had fought a proxy war in a third country. This proxy war or limited war strategy would be a feature of other Cold War conflicts, for example the Vietnam War.
As a result of the Korean War and General MacArthur’s dismissal, the strategy of roll back was largely discredited. However, the temporary division of Korea along the 38th parallel was a success for the policy of containment, as communism didn’t spread into South Korea.
Even after fighting in Korea had stopped, US soldiers remained stationed in South Korea, which was an irritation for the Chinese government and put pressure on relations between the two countries.