Henry Lewis Stimson, secretary of war, once remarked that “gentlemen do not read each other’s mail.” This observation did not apply to the Zimmermann telegram of 1917. Arthur Zimmermann was a member of the German Diplomatic Corps since 1908. He had risen to the position of secretary of state for foreign affairs in 1916. During World War I, the German government had petitioned the U. S. State Department to use its cable lines to communicate with its foreign missions about President WoODROW Wilson’s mediation proposals. Secretary Zimmermann sent a coded cable via the American embassy in Berlin to the United States. The State Department in Washington, which handed it to the German ambassador, then cabled it to the German embassy in Mexico City.
Unfortunately for the Germans, the British intercepted the cable, deciphered it, and presented it to the Americans. The British government hoped that the message would hasten American involvement in the war. The cable informed the German ambassador in Mexico City that his government planned to resume unrestricted submarine warfare on February 1, 1917. It announced that the German government was repudiating a policy established in the wake of the sinking of RMS Lusitania. Additionally, the cable further proposed to the Mexican government a Mexican-German alliance in which Mexico was urged to reconquer territory lost to the United States. In the 1840s Mexico had lost land in Texas and California as a result of the Mexican-American War of 1846-48. Kidnappings of American dignitaries and raids by the Mexican leader Pancho Villa had caused tension between the two nations. President Wilson found it difficult to maintain a policy of noninterference, given the upheaval in Mexico.
Wilson finally sent an expedition led by General John Pershing to locate and kill Pancho Villa. The army did not operate effectively in Mexico, which is one reason that Germany probably felt it could risk war with the United States. The expedition, popularly known as the Mexican Invasion, failed to capture Pancho Villa. The American army withdrew in January of 1917. Despite the army’s defeat, Mexican leaders were furious with the U. S. intervention. The Mexican president, Venustiano Carranza, even proposed an alliance to Germany. As the war situation worsened for Germany, it became increasingly interested.
When the deciphered telegram was published on March 1, 1917, it further intensified anti-German feeling in the United States. Shortly after the Zimmermann telegram was made public, German U-boats sank four unarmed American merchant vessels in the first two weeks of March. Wilson lost his gamble that the United States could pursue neutral trade without being brought into the European war.
Those favoring neutrality claimed that the note was a forgery. Zimmermann himself, however, admitted that the telegram was genuine. The publication of the note was central to eliciting public support for the war. Without the telegram the United States might have delayed entering the war; Germany’s decision to once again engage in unrestricted submarine warfare against the British blockade, however, guaranteed that the United States, largely sympathetic to the Allies, would declare war on Germany. The Zimmermann telegram was the catalyst that set the U. S. war effort in motion.
Further reading: Barbara Tuchman, The Zimmermann Telegram (New York: Macmillan, 1996).
—Paul Edelen
World History
