Answer:
He wanted to prevent the advance of communism.
Step-by-step explanation:
The Korean War was fought under the context of the Cold War. A conflict between the Soviet Union and the United States.
The Korean War sides were North Korea, supported by China and the Soviet Union and South Korea, supported by the United Nations especially by the United States. Korea was split into two territories, one under the control of the communism and the other capitalist. Both governments claimed that they ruled over all the country.
I hope this answer helps you.