Which event ended the United States' policy of isolationism in the 1940s? The Gulf War
OB.
The Cold War
World War II
D.
World War

World War II

Explanation:

World War I was supposed to be “the war to end all wars”. All countries, the United States included, suffered many losses and did not want to go through that tragedy again.

This is why the United States has declared a policy of isolation. The idea was not to get involved in foreign affairs, avoid military conflicts, and remain neutral and peaceful. At the start of World War II, they were still determined to keep this policy.

Yet with the progression of the war, and most significantly with the attack on Perl Harbor, the United States felt threatened and realized they need to protect the democracy in the Allied countries. Nazi Germany was advancing and taking hold of more countries, and the United States realized it is time to end isolation policy and get involved in order to stop the advancing enemy.

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