United States declaration of war on Germany (1917)

The United States declared war on the German Empire on April 6, 1917. PresidentWoodrow Wilson asked a special joint session of the United States Congress for a declaration of war on April 2, 1917, which passed in the Senate on the same day and then in the House of Representatives four days later on April 6. Wilson signed it into law the same day, making the United States officially involved in the First World War.

Despite heavy opposition to the war initially, several incidents resulted in the United States public largely turning against Germany and its allies by 1917. In his speech to the Congress, Wilson stated that the war would make the world ''safe for democracy'' and cited the German Empire's decision to resume unrestricted submarine warfare as an attack on not only Europe, but the United States as well.