What caused the United States to enter World War I in 1917?
BACK
German unrestricted submarine warfare against American merchant ships and the interception of the Zimmerman Telegram proposing a German-Mexican alliance.
FRONT
What caused the United States to enter World War I in 1917?
BACK
German unrestricted submarine warfare against American merchant ships and the interception of the Zimmerman Telegram proposing a German-Mexican alliance.
