United States in World War I

The United States declared war on Germany on April 6, 1917, over 2​¹⁄₂ years after World War I started. A ceasefire and Armistice was declared on November 11, 1918. Before entering the war, the U.S. had remained neutral, though it had been an important supplier to Great Britain and the other Allied powers.

The U.S. made its major contributions in terms of supplies, raw material and money, starting in 1917. American soldiers under General John Pershing, Commander-in-Chief of the American Expeditionary Force (AEF), arrived in large numbers on the Western Front in the summer of 1918. During the war the U.S. mobilized over 4 million military personnel and suffered 110,000 deaths, including around 45,000 who died due to the 1918 Spanish flu outbreak (30,000 before they even reached France). The war saw a dramatic expansion of the United States government in an effort to harness the war effort and a significant increase in the size of the U.S. Armed Forces.

After a relatively slow start in mobilizing the economy and labor force, by spring 1918, the nation was poised to play a role in the conflict. Under the leadership of President Woodrow Wilson, the war represented the climax of the Progressive Era as it sought to bring reform and democracy to the world, although there was substantial public opposition to U.S. entry into the war.

The American entry into World War I came in April 1917, after more than two and a half years of efforts by President Woodrow Wilson to keep the United States out of the war. Apart from an Anglophile element urging early support for the British, American public opinion reflected that of the president: the sentiment for neutrality was particularly strong among Irish Americans, German Americans and Scandinavian Americans, as well as among church leaders and among women in general. On the other hand, even before World War I had broken out, American opinion had been more negative toward Germany than towards any other country in Europe. Over time, especially after reports of atrocities in Belgium in 1914 and following the sinking of the passenger liner RMS Lusitania in 1915, the American people increasingly came to see Germany as the aggressor in Europe.

As U.S. President, it was Wilson who made the key policy decisions over foreign affairs: while the country was at peace, the domestic economy ran on a laissez-faire basis, with American banks making huge loans to Britain and France — funds that were in large part used to buy munitions, raw materials and food from across the Atlantic. Until 1917, Wilson made minimal preparations for a land war and kept the United States Army on a small peacetime footing, despite increasing demands for enhanced preparedness. He did however expand the United States Navy.

War declared

In January 1917, Germany resumed unrestricted submarine warfare. The German Foreign minister, Arthur Zimmermann invited revolution-torn Mexico to join the war as Germany's ally against the United States in the Zimmermann Telegram. In return, the Germans would send Mexico money and help it recover the territories of Texas, New Mexico and Arizona that Mexico lost during the Mexican–American War 70 years earlier. British intelligence intercepted the telegram and passed the information on to Washington. Wilson released the Zimmerman note to the public and Americans saw it as a casus belli—a cause for war.

At first, Wilson tried to maintain neutrality while fighting off the submarines by arming American merchant ships with guns powerful enough to sink German submarines on the surface (but useless when the U-boats were under water). After submarines sank seven US merchant ships, Wilson finally went to Congress calling for a declaration of war on Germany, which Congress voted on April 6, 1917.

As a result of the Russian February Revolution in 1917, the Tsar abdicated and was replaced by a Russian Provisional Government. This helped overcome Wilson's reluctance to having the US fight alongside a country ruled by an absolutist monarch. Pleased by the Provisional Government's pro-war stance, the US accorded the new government diplomatic recognition on March 9, 1917.

Although the United States declared war on Germany on April 6, 1917, it did not initially declare war on the other Central Powers, a state of affairs that Woodrow Wilson described as an "embarrassing obstacle" in his State of the Union speech. Congress declared war on the Austro-Hungarian Empire on December 7, 1917, but never made declarations of war against the other Central Powers, Bulgaria, the Ottoman Empire or the various co-belligerents allied with the Central Powers. Thus, the United States remained uninvolved in the military campaigns in central and eastern Europe, the Middle East, the Caucasus, North Africa, Sub-Saharan Africa, Asia and the Pacific.

Propaganda

Crucial to US participation was the sweeping domestic propaganda campaign executed by the Committee on Public Information, overseen by George Creel. The campaign consisted of tens of thousands of government-selected community leaders giving brief carefully scripted pro-war speeches at thousands of public gatherings. Along with other branches of government and private vigilante groups like the American Protective League, it also included the general repression and harassment of people either opposed to American entry into the war or of German heritage. Rumors about a German-induced attempt to start uprising among Black Americans caused a wave of lynchings to occur in the Southern United States. Other forms of propaganda included newsreels, photos, large-print posters (designed by several well-known illustrators of the day, including Louis D. Fancher and Henry Reuterdahl), magazine and newspaper articles, and billboards.

Children

The nation placed a great importance on the role of children, teaching them patriotism and national service and asking them to encourage war support and educate the public about the importance of the war. The Boy Scouts of America helped distribute war pamphlets, helped sell war bonds, and helped to drive nationalism and support for the war.

After the war

The government promptly cancelled wartime contracts, ended the draft, and started to bring home its troops from Europe as fast as transport became available. However there was no GI Bill or financial or educational benefits for veterans, and the lack became a major political issue, especially for the large veterans' groups such as the Veterans of Foreign Wars and the new American Legion. The readjustment period was marked by soaring unemployment, massive strikes, and race riots in 1919. The public demanded a return to "normalcy", and repudiated Wilson with the election of conservative Republican Warren G. Harding.