Answer:
When World War I broke out across Europe in 1914, President Woodrow Wilson proclaimed the United States would remain neutral, and many Americans supported this policy of nonintervention. American companies, however, continue to ship food, raw materials and munitions to both the Allies and Central Powers, although trade between the Central Powers and the U.S. was severely curtailed by Britain’s naval blockade of Germany. U.S. banks also provided the warring nations with loans, the bulk of which went to the Allies.
On May 7, 1915, a German submarine sank the British ocean liner Lusitania, resulting in the deaths of nearly 1,200 people, including 128 Americans. The incident strained diplomatic relations between Washington and Berlin and helped turn public opinion against Germany.
A German U-boat torpedoed a French passenger ship, the Sussex, killing dozens of people, including several Americans. Afterward, the U.S. threatened to cut diplomatic ties with Germany.
On April 2, 1917, Wilson went before a special joint session of Congress and asked for a declaration of war against Germany, stating: “The world must be made safe for democracy.”
In early 1917, the U.S. Army had just 133,000 members. That May, Congress passed the Selective Service Act, which reinstated the draft for the first time since the Civil War and led to some 2.8 million men being inducted into the U.S. military by the end of the Great War. Around 2 million more Americans voluntarily served in the armed forces during the conflict.
The first U.S. infantry troops arrived on the European continent in June 1917; in October, the first American soldiers entered combat, in France. That December, the U.S. declared war against Austria-Hungary (America never was formally at war with the Ottoman Empire or Bulgaria).
When the war concluded in November 1918, with a victory for the Allies, more than 2 million U.S. troops had served at the Western Front in Europe, and more than 50,000 of them died.
