I assume that there must be a greater example of diplomatic folly than the Zimmermann Telegram, but I cannot think of it at the moment. Believing that the entry of the US into the Great War was inevitable with the planned resumption by Germany of unrestricted submarine warfare against neutral shipping, the German Foreign Secretary Arthur Zimmermann on January 11, 1917 sent the following telegram in code to the German ambassador to Mexico Heinrich von Eckardt:
- “We intend to begin on the first of February unrestricted submarine warfare. We shall endeavor in spite of this to keep the United States of America neutral. In the event of this not succeeding, we make Mexico a proposal of alliance on the following basis: make war together, make peace together, generous financial support and an understanding on our part that Mexico is to reconquer the lost territory in Texas, New Mexico, and Arizona. The settlement in detail is left to you. You will inform the President of the above most secretly as soon as the outbreak of war with the United States of America is certain and add the suggestion that he should, on his own initiative, invite Japan to immediate adherence and at the same time mediate between Japan and ourselves. Please call the President’s attention to the fact that the ruthless employment of our submarines now offers the prospect of compelling England in a few months to make peace.” Signed, ZIMMERMANN
The sheer madness of this cannot be overstated. Mexico was still in the throes of the Mexican Revolution and posed no threat to the US. The US had recently demonstrated that it could dispatch military forces into Mexico with impunity. Threatening the physical integrity of the US converted a far off European conflict into a direct threat against the US. If the US did intervene in the Great War, an additional conflict with Mexico would barely resister in regard to the immense military mobilization that the US would undergo.