Why did the United States enter World War I, and what
impact did the war have on the nation?

The U.S. entered World War I because Germany embarked on a deadly gamble. Germany sank many American merchant ships around the British Isles which prompted the American entry into the war. World War one had huge effects on America including highly productive industry that preceded the Great Depression, jobs given to woman, which helped pass the nineteenth amendment, and a new kind of diplomacy and antiwar sentiment that affected America's entrance into World War II.

c. free trade can lead to low pay for workers in poorer countries.

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