UNITED STATES DECLARES WAR ON GERMANY

United States declares war on Germany

Four days after Wilson’s address, Congress approved the declaration of war, formally bringing the United States into World War I on the side of the Allies. The decision triggered a sweeping mobilization effort at home, including the enactment of the Selective Service system to raise a large national army. The American Expeditionary Forces, under General John J. Pershing, began forming and preparing for deployment to the Western Front, where trench warfare and modern weapons had already devastated European armies. Navy and merchant marine forces also moved quickly to help escort convoys across submarine-infested waters. For American society, the declaration meant new demands for industrial production, food conservation, and public support of the war effort, along with contentious debates about civil liberties and dissent. Militarily, the arrival of fresh American troops and resources helped stiffen Allied resolve, contributing to the eventual collapse of German hopes for victory and shaping the postwar order in which the United States would remain a significant military and economic power.