What lead to the United States involvement in World War One?

When World War One began in 1914, Americans wanted nothing to do with it. The national government agreed with the people and proclaimed our neutrality. As the war went on, the United States found it harder to remain neutral. Their attachment to Mother England made them more sympathetic to the Allies, but they would not let their attachment pull them into war. The popular opinion of the United States citizens was to still stay out of World War One but other nations, specifically Germany, would not respect our neutrality. Germans sank US passenger boats, like the Lusitania, and sent the Zimmerman telegram to Mexico and both these things angered us. The thing that was one of the big causes of our entrance into the war was Germany's unrestricted submarine warfare.

Germans had u-boats and they used these to ensure they had the upper hand in the war. Germans warned that they would attack any boat they saw as a threat, including passenger boats.

LUSITANIA (LOC)

Lusitania 1907

United States

Many Americans disregarded the threat and still boarded passenger ships. The Lusitania was a passenger ship that many Americans were abroad and the Germans sank it. This angered Americans because the Germans were no killing our people not just sinking commercial boats. We asked Germany to stop sinking our passenger boats but they refused.

In January 1917, the British intercepted a telegram being sent by Germany to Mexico. In the telegram Germany said if Mexico helped Germany defeat the United States then they would help Mexico get their land back from the United States. Although it is argued that the Zimmerman telegram was fake and simply a ploy by England to get the United States involved in the war, it did get the United States involved in the war.

One of the big reasons the United States...