9.5The Great War

When World War I erupted in Europe in 1914, the United States tried to stay neutral. But German submarine warfare, which sank ships carrying Americans, and other provocations pushed opinion toward war. In 1917 the country entered the conflict on the side of Britain and France.

Fresh American troops and resources helped tip the balance toward Allied victory in 1918. President Wilson then championed an idealistic peace, including a League of Nations to prevent future wars, set out in his Fourteen Points.

The world must be made safe for democracy.

But the Senate, wary of foreign commitments, rejected the League. America retreated toward isolation, even as it had become a decisive global force.