At the end of January 1917, the German government—desperate to break the stalemated trench warfare—announced that it would resume unrestricted submarine attacks. The United States broke diplomatic relations with Germany and further events pushed the nation even closer to war. On March 1, newspapers published a telegram from German foreign minister Arthur Zimmermann to the Mexican government, proposing a German-Mexican alliance against the United States. (For attacking the United States, the Mexicans would recoup lost territory in Texas, New Mexico, and Arizona.) Intercepted by the British, the telegram was published widely in American newspapers and inflamed popular opinion against the Germans.
FROM 2nd from London # 5747.
“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 or 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.”
Source: National Archives.
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