What was the u. s's role in ww1, also, describe it, !

Up until April 2nd, 1917 the U.S. had only traded with European nations, including those engaged in the war. Wanting to keep to an isolated existence, the president decided to avoid combat with the full support of the people behind him. Since the U.S. traded with both sides they attempted to act as a mediator between sides in order to get Britain to remove the blockade on Germany. However, after Germany attacked the Lusitania on which 128 Americans were killed, America removed all communications with Germany. This escalated to America declaring war on Germany and entering the war on the side of the Allies on April 6th, 1917. An armistice was declared on November 11th, 1918. Only a year and a half after the U.S. entered.