Final answer:
The delayed U.S. entry into World War I was a result of isolationism as a foreign policy.
Step-by-step explanation:
The correct answer is isolationism. Isolationism refers to a policy of avoiding involvement in the political and military affairs of other countries. In the case of the United States, isolationism was a dominant foreign policy stance prior to its entry into World War I. The US government, under President Woodrow Wilson, initially pursued a policy of neutrality and sought to stay out of the war.
This changed over time as certain events occurred, such as the sinking of the RMS Lusitania by a German submarine, which led to growing public sentiment in favor of the US entering the war. Ultimately, it was the combination of various factors, including the violation of American neutrality and the Zimmermann Telegram, that prompted the US to abandon its isolationist stance and enter World War I.
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