The Zimmermann telegram in January of 1917 was a decisive factor in the United States entering World War I. This was because the proposal in the telegram to Mexican government officials stated that Mexico would recover the lost territories of Arizona, New Mexico and Texas if they were to form an alliance with Nazi Germany. The public was outraged by the idea, but also the proposal to Mexico helped Americans to realize that Germany posed a real threat to them, and the democracy that they lived under. If the Germans one, then it could be expected that the German-Mexican partnership would control parts of America much the way they were controlling parts of France and other countries. The Mexican-American war was fought just seven decades before, and therefore this was a situation that still in the forefront of American memory. To avoid the potential for German or Mexican occupation, the American people were ready to fight.
The telegram was sent by Arthur Zimmermann, who was the Foreign Secretary for Germany. It was highly encrypted, and it was intended as a secret communication between the governments of Germany and Mexico. The American government wanted to use it to support the movement to enter the war, but many Americans were against this. The war was far away in Europe, and for many in the population it amounted to spending effort and resources to fight foreign battles that had nothing to do with the American people. The Zimmerman telegram made it personal, especially when the Germans publicly stated that the telegram had been correctly decoded, and the Germans were seeking a partnership with Mexico to support their war efforts. Mexico had been neutral to the war in Europe. The Americans had been neutral as well, but the potential attack by either Mexico or Germany was enough to encourage Americans to support proactive measures by allying with Great Britain in the war effort.
- Goldstein, Donald M., and Harry J. Maihafer. America in World War I: The Story and Photographs. Washington, D.C.: Brassey’s, 2004.eBook Collection. 2004.