The decoding of the Zimmerman Telegraph was a principal factor in getting the US to enter World War I in 1917. The telegraph was sent from Arthur Zimmerman, a German foreign secretary, to a German ambassador in Mexico. In the coded message (see image), a proposal was made that Mexico declare war against the US in exchange for financial benefits and lost territory. The British then intercepted the message, eventually decoding and providing its contents to President Woodrow Wilson. Check out the decoded Zimmerman Telegraph on the next page.
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