Final answer:
The United States restored isolationism after World War II due to the desire to avoid costly involvement in global conflicts and the fear of communism spreading. They believed that by maintaining isolationism, they could protect their own security and interests.
Step-by-step explanation:
After World War I, the United States adopted a policy of isolationism, which meant that they were mainly focused on their own domestic affairs and avoided getting involved in world affairs. However, after World War II, the United States restored isolationism due to a combination of factors. One reason was the desire to avoid the costly involvement in global conflicts, as the United States had just emerged from a devastating war. Another reason was the fear of communism spreading and the need to protect American interests against the Soviet Union. The United States believed that by maintaining a policy of isolationism, they could safeguard their own security and interests.
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