What year did the Zimmerman Telegram come out?

Answer 1

The Zimmerman Telegram "came out" in 1917.

It was first sent, in code, on January 16, 1917, and was promptly intercepted and deciphered by the British, who were already fighting the Germans. They showed it to members of the U.S. Embassy in London in the middle of February, and a few days later it was shown to President Woodrow Wilson.

The Germans had already resumed their unrestricted submarine attacks on British merchant and passenger ships around February 1, causing many civilian deaths. Some of those who died were American passengers. These deaths, along with the offer made to Mexico in the Zimmerman Telegram to assist them in invading and reclaiming Southwestern States that the U.S. had won from Mexico decades before, finally ended the isolationism and pacifism that had prevailed in the U.S. for the previous part of the war.

The Zimmerman Telegram was one of the major factors that caused the U.S. to declare war on Germany on April 6, 1917.