Germany's Betrayal is an ABOMINATION!!
After the loss of so many innocent lives due to Germany's move in the war, we had them sign the Sussex Pledge, putting certain restrictions on their fighting. Germany now has to warn and safely remove passengers and crew before they attack, so that we can save lives.
A Conspiracy Between Germany and Mexico is the Last Straw
The Zimmerman Note was intercepted by the British on it's way to Mexico from Germany, sparking an outrage in America. The telegram told Mexico that if they joined the war against America, they would get New Mexico, Texas, and Arizona back.