The Zimmermann telegram helped change Americans' opinions about involvement in the first world war because the telegram revealed German plans to form an alliance with Mexico and Japan.
The Zimmermann Telegram was a device that encrypted the deciphered messages of the German military to the American intelligence. The Zimmermann telegram largely helped influence the global opinion of American involvement in the World Wart I. This was because the telegram had revealed about the plans of Germany, Mexico, and Japan to constitute an alliance if a war is declared by America.
Learn more about the Zimmermann telegram here:
https://brainly.com/question/26349428
#SPJ4
