To what extent was US intervention in to Korea purely a response to communist aggression?

A-Level: History

On the 25th of June 1950, a communist North Korea invaded South Korea in a totally unprovoked attack. President Truman and his government went to the United Nations in order to liberate South Korea, and the UN Security Council passed a resolution sanctioning intervention by UN & US forces. This resolution could have been vetoed by the Soviets but they were absent during the vote due to a boycott of the UN. The attack on South Korea came as a surprise to the western nations. In the previous week a congressman had told congress that no such war was likely.
President Truman had decided to go to war for many reasons, but one of his main reasons was due to his critics labelling him as being “soft” on communism, one of these critics was Senator Joseph McCarthy. The fact that china had turned communist did not help President Truman’s image and added further weight to his critics claim. But some may argue that china was not Americas to loose but in any case one of the largest countries in the world with a large population had turned communist over night. In relation to the question if intervention in Korea was purely a response to communist aggression, President Truman may have gone to war due to the fact that he was trying to sway public opinion and not as a response to communist aggression.
Containment was a policy that President Truman truly believed in. Containment is the notions that by not letting communism expand that it will have nowhere to go and therefore suffocate its self.
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