Why did the United States decide to enter World War I?

Explanation:

Its declared decision on 31 January 1917 to target neutral shipping in a designated war-zone became the immediate cause of the entry of the United States into the war. ... Outraged public opinion now overwhelmingly supported Wilson when he asked Congress for a declaration of war on April 2, 1917.

The U.S entered WW1 for several reasons. The U.S entered for two main reasons: one was that the Germans had declared unlimited German submarine warfare and the Zimmermann note.

Explanation:

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