Final answer:
The United States intervened in World War I due to the German submarine warfare, the Zimmerman Telegram, and President Woodrow Wilson's belief in spreading democracy.
Step-by-step explanation:
The United States chose to intervene in World War I primarily due to several factors. Firstly, the German unrestricted submarine warfare campaign, which targeted American merchant ships, resulted in a loss of American lives and threatened U.S. economic interests. Secondly, the interception of the Zimmerman Telegram, where Germany sought an alliance with Mexico against the U.S., further pushed the U.S. towards intervention. Lastly, the ideological motivation of President Woodrow Wilson's belief in spreading democracy and making the world safe for democracy played a significant role in the decision to join the war.
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