The United States initially practiced isolationism at the beginning of WWI, though they did sell weapons and provide some aid to other countries. Germany sinking the Lusitania in 1915 was the main reason the US entered the war in April 1917. With new US troops, the tide turned in favor of the Allies. The US fought in major battles on the Western Front and had around 323,018 casualties over the two years they were involved in the war. President Wilson outlined his Fourteen Points speech in 1918 to promote the US was fighting for a moral cause and peace. After the war, the US emerged as a very powerful, strong, and rich country.