Why did President Truman respond as he did to the Korean War?
There were at least three important responses by Truman to this war.
First, he chose to seek UN intervention rather than simply acting alone. He did this in part to show international support for the war and partly because the US had no treaty with South Korea that would justify entering the conflict alone.
Second, he chose not to ask Congress to declare war. He did this because he did not want to escalate the war by making it formal.
Finally, he fired General MacArthur and chose not to attack China like MacArthur wanted. This was because he did not want a broader war, one that might end up being much longer and more costly. In addition, this shows Truman following the strategy of containing communism rather than trying to destroy it.