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USA Entry in World War I

Why Did USA Join World War I ?
Initial Neutrality
With the outbreak of World War I, the United States had taken a strictly neutral stance. President Woodrow Wilson had said that the United States "must be neutral in fact as well as in name."

Read President Woodrow Wilson’s Declaration of Neutrality, August 19, 1914

Despite the declaration by President Wilson, the United States saw the rise of propaganda for both the Central and Allied Powers. The lobby favoring the German cause gradually died down and Britain was seen as a “cultural brother.” The autocratic monarchy of Germany was viewed with much suspicion among the masses. Popular sentiments supported the Allied Powers.

Fallout of Submarine Warfare
By the year 1915, Germany had taken recourse to unrestricted submarine warfare. In an attempt to isolate Britain, German submarines had taken to attacking all passenger and cargo vessels bound to the shores of Britain. On May 7, 1915, the German U–boat, U-20 torpedoed RMS Lusitania, the British Royal Mail Ship, off the coast of Ireland. Among the many passengers aboard the Lusitania, 128 Americans were killed. A huge outcry ensued and the United States was in favor of joining the war. Following this, Germany halted unrestricted submarine warfare until 1916, when the Housatonic, an American cargo ship carrying supplies to Britain was sunk.

Zimmerman Telegram
In 1917, German Foreign Minister Alfred Zimmerman tried to eliminate the threat posed by U.S. entry into World War I by provoking Mexico to attack the United States. The attempt was to instigate Mexico to reclaim territory lost in the Mexican-American War, which included parts of Texas, Arizona, and New Mexico. This would keep the United States engaged in war and deter its entry into World War I. The coded telegram was intercepted and decoded by British intelligence, who passed the telegram on to the United States. On March 1, 1917, the contents of the telegram were released by the press, and Americans turned firmly in favor of joining the Allied cause.

Change of Stance
The Zimmerman telegram was sent to the United States by Britain to urge America to enter the fray. President Wilson, who had been re-elected in 1916 with the slogan “He kept us out of war,” sought Congress’ approval to go to war on April 2, 1917. On April 6, Congress approved and the United States declared war on Germany. With the United States came state-of-the-art weapons and troops. Enhanced mobility and renewed vigor led to an Allied victory on the Western Front. The U.S. entry into World War I was a major cause of the downfall of the Central Powers.

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