Answer: In 1947, President Harry S. Truman pledged that the United States would help any nation resist communism in order to prevent its spread. His policy of containment is known as the Truman Doctrine. ... To help rebuild after the war, the United States pledged $13 billion of aid to Europe in the Marshall Plan.
Explanation:
I’m pretty sure the answer is C) Fear of the “end of the world”
Create an international peacekeeping organization. AKA League of Nations