Answer:
The United States got involved in WWI in 1917 after a series of events led to a breakdown in diplomatic relations with Germany.
Step-by-step explanation:
The United States got involved in WWI in 1917 after a series of events led to a breakdown in diplomatic relations with Germany. The most significant of these events was the sinking of the British passenger ship Lusitania by German U-boats in 1915, as well as Germany's introduction of unrestricted submarine warfare in the Atlantic Ocean. In early 1917, the British intercepted the Zimmermann Telegram, a communication from the German Foreign Minister proposing a military alliance with Mexico against the United States. This event, combined with Germany's declaration of war on the United States, convinced President Woodrow Wilson to ask Congress to declare war on Germany. Congress responded by passing a joint resolution on April 6, 1917, officially declaring war on Germany and entering the United States into WWI.