American Military History, Volume 2 by Richard W. Stewart

On April 2, 1917, President Woodrow Wilson addressed Congress, asking for a declaration of war against Germany. Just over two months earlier, on January 31, the German government had announced its resumption of "unrestricted subma- rine warfare." With the announcement, German U-boats would with- out warning attempt to sink all ships traveling to or from British or French ports. Under the new strategy, U-boats had sunk three Ameri- can merchant ships with a heavy loss of American life in March 1917. Two days after Wilson's speech, the Senate overwhelmingly declared that a state of war existed between Germany and the United States. Two days later the House of Representatives followed suit. The Unit- ed States had entered "the Great War."

Since the United States went to war over the limited issue of Ger- many's submarine warfare, the Wilson administration conceivably could have taken only a naval role against the German submarines. That role, however, never received fervent support from the Allied or the U.S. Army's leadership. Pressure from both the British and French leaders urged Wilson to reinforce the Western Front that stretched from Bel- gium to Switzerland. Despite the carnage, the Army's military leaders and planners saw the Western Front as the only place that the United States could play a decisive role in defeating Germany. That participa- tion in the decisive theater would give Wilson a larger role and greater leverage in deciding the peace that followed. Thus it would be on the battlefields and in the trenches of France that the U.S. Army would fight in 1917 and 1918.