Which of the following made it easy for the united states to supply its efforts in world war 1?

First, I need more details. But I can still give you the answer. The United States got involved in World War 1 because of a Zimmerman telegram sent to Mexico detailing German plans against the U.S in which Mexico was conquered by the U.S loosing Arizona, New Mexico, and Texas. The note was sent on April 2 1917 and 4 days later the U.S declared war against Germany.

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