The communist victory in China in 1949 and the Sino-Soviet alliance made Asia a second front of the Cold War.
In October 1949, Mao Zedong proclaimed the People's Republic of China after the Chinese Communist Party defeated the Nationalists, who retreated to Taiwan. Many Americans saw this as the "loss of China", and the Truman administration faced fierce criticism at home.
In February 1950, Mao and Stalin signed the Sino-Soviet Treaty of Friendship and Alliance. The two largest communist states were now formally allied. To Washington, communism looked like a single bloc expanding in Asia.
The balance of power was shifting. The USSR had tested an atomic bomb in August 1949, ending the US monopoly. In January 1950, Secretary of State Dean Acheson described a US "defensive perimeter" in the Pacific. It did not mention Korea. Communist leaders may have read this as a sign that the USA would not fight for it.
In April 1950, the secret report NSC-68 argued that the Soviet Union sought to extend its authority across the world. It called for a rapid build-up of American military, political and economic strength. Truman did not fund it fully until war broke out in Korea.
- People's Republic of China
- Proclaimed October 1949.
- Sino-Soviet Treaty
- February 1950.
- Acheson's perimeter speech
- January 1950; Korea left out.
- NSC-68
- April 1950; calls for a rapid military build-up.
Worked example: Explaining why Asia mattered after 1949
An essay asks why the Cold War spread to Asia.
- Event: the communist victory in China changed the balance of power in Asia.
- Alliance: the 1950 Sino-Soviet Treaty made communism look like a united bloc.
- Perception: US leaders, under domestic pressure, feared further communist gains.
- Result: Asia became a second front where the USA applied containment.
Watch out for this
The USA had always planned to defend South Korea.
Acheson's January 1950 speech left Korea outside the defensive perimeter. The decision to fight was a response to the invasion in June 1950.
Check your understanding
Why did the communist victory in China raise US fears in 1949-50?
- It seemed to create a united communist bloc after the Sino-Soviet Treaty of 1950.
- China immediately invaded Japan.
- China joined the United Nations Security Council.