2. Zimmerman Telegram: In early 1917, the British intercepted and decoded a telegram from German Foreign Secretary Arthur Zimmermann to the German ambassador in Mexico. The telegram proposed an alliance between Germany and Mexico against the United States if the U.S. entered World War I. The publication of the Zimmermann Telegram further inflamed anti-German sentiment in America.
3. Unrestricted Submarine Warfare: Germany's resumption of unrestricted submarine warfare in 1917 was a major factor in the United States' decision to enter World War I. In January 1917, Germany announced that it would sink all ships, including merchant vessels, in a designated war zone around the British Isles. This aggressive policy put American trade and the lives of American citizens at risk.
4. Attack on American Merchant Ships: Throughout the war, German U-boats attacked and sank several American merchant ships, resulting in the loss of American lives and disruption of trade. Notable incidents include the sinking of the SS Gulflight in June 1917 and the SS Housatonic in February 1918.
5. American Isolationism: Although many Americans initially advocated for strict neutrality and non-intervention in the war, a combination of emotional, economic, and moral factors gradually drew the United States into the conflict. President Woodrow Wilson initially sought to mediate and end the war through diplomacy, but the escalation of events and Germany's actions made neutrality increasingly difficult to maintain.