What cause the U.S to enter into World War 1?

Answer 1

Nothing forced the US to join WW1. They just wanted to make sure that their allies were safe.

Zaragotha (Zara)

During World War 1, british intelligence intercepted a telegram sent from the German forces to Mexico. This was known as the Zimmerman Telegram. In this message, Germany asked for Mexico to attack the U.S., to distract them from joining the war in Europe to help their allies. Mexico replied no, because of past loss in a war against the U.S.

There was also The Sussex Pledge, a promise which Germany broke, stating that they could not use unrestricted submarine warfare.

Cyress

Answer 2

America entered the war because they intercepted a telegram caled the Zimmerman (i think) telegram that the german's were going to send to Mexico asking them to join the war and help them defeat America (in return they could have Texas and New York) and that was the last straw for America and so in 1917 they Declared War on Germany!