The resumption of unrestricted submarine warfare by Germany (C) was one of the major reasons why Wilson decided to declare war against Germany. The U.S. had stayed out of the war and sought to bring about a negotiated solution. However, after Germany began unrestricted submarine warfare against all ships near Europe of any power the U.S. cut off diplomatic relations. Then following the sinking of 3 U.S. ships on March 18, 1917, President Wilson requested that Congress declare war on April 2, 1917.
