Lenin signs a treaty w/ Germany, Causing Russia to leave the war
Germany sinks the City of Memphis, Illinois, and the Vigilancia
Czar Nicholas II abdicates
Being associated with an autocratic government made American hesitant to join a war on the side of Russia. After the Russian Reveloution, this problem no longer exsited.
America formally decares war on the side of the Allies
The Selective Service Act is passed
Germany advances past trenches, into Allied territory
USMC and Army stop German troops at Belleau Wood and Chateau-Thierry