Question

7. What caused the United States to join the Allies in fighting World War I?

Answer 1

The Germans' unrestricted use of submarines

Answer 2

The sinking of the Lusitania which is a pasenger ship being attacked due to Germany's unrestricted submarine acces and the Zimmerman telegram also drew U.S. into World War I.

Answer 3

I would agree with Turtlegirl. The sinking of the Lusitania is something that it always talked about but it was the Zimmerman telegraph was the last straw that lead to the US delcaration of war on Germany.