The most colossally stupid and historically consequential mismanagement of classified war plans in an electronic transmission belongs to Arthur Zimmermann, the German foreign minister who dispatched an encrypted telegram to Mexico, via Western Union, offering Texas, Arizona, and New Mexico as a war trophy if Mexico would side with Germany in the First World War.
The diplomatic dispatch, dated January 17, 1917, was part of Zimmermann’s foreign-policy strategy, which was as ambitious as it was delusional. Two years earlier, Zimmermann had cautioned James Gerard, the American ambassador in Berlin, about the potential for “a half million trained Germans” living in the United States to mobilize their Irish-immigrant counterparts in a revolution to overthrow the U.S. government. “I thought at first he was joking,” Gerard reported to the State Department, “but he was actually serious.”
Zimmermann considered himself an authority on the Americans based on a train trip he had taken across the U.S. in 1904. Zimmermann felt that the best way to keep the United States out of the war in Europe was to create enough disturbance along the U.S.-Mexico border to distract the Americans from the conflict happening across the Atlantic. To this end, Zimmermann had helped finance Pancho Villa’s infamous cross-border raid on Columbus, New Mexico, in 1916, and he had encouraged William Randolph Hearst to make a silent-movie series—released in January 1917—about Japanese spies who ally themselves with Mexicans in a plot to invade the United States. Episode 10 of the series, which was called Patria, features an all-out Japanese assault on New York City.
In February 1917, Germany had decided to reintroduce unrestricted submarine warfare, following a year-and-a-half hiatus after the sinking of the Lusitania by a German U-boat, which had killed 1,195 innocent civilians, including 123 Americans. Zimmermann feared that the renewed attacks on passenger ships could provoke the United States to side with the Allies. To prepare for this contingency, Zimmermann devised a plan that, as outlined in his telegram, called for the Germans to enlist Mexico and Japan in an invasion of the United States, with the understanding that Germany would allow Mexico to annex the southwestern corner of the country.
Normally, Zimmermann would have dispatched such a sensitive diplomatic “instruction” via one of five German-owned transatlantic cables, which would have guaranteed secure transmission of the message. But the British had cut all five cables at the outset of the war, forcing the Foreign Office to encode its communications and dispatch them over wireless or through other means. Zimmermann was so confident of the strength of German encryption that he not only dispatched his telegram over wireless, via Sweden, but sent an additional copy via the American embassy in Berlin. What Zimmermann had not anticipated was that a team of British code breakers was intercepting wireless communications and decrypting them in a secret location, known simply as Room 40, in the British Naval Office. When the “Zimmermann telegram” arrived in Room 40, on the morning of January 17, the two on-duty cryptologists began deciphering the message and immediately summoned Admiral Reginald Hall.
“Do you want America in the war, sir?” one of the cryptologists asked.
“Yes, why?” Hall replied.
“I’ve got a telegram that will bring them in if you give it to them.”
The British government had been trying to persuade the United States to join France and Britain in the war against the Germans since 1914, but the American people, along with their Congress and their president, Woodrow Wilson, remained decidedly isolationist. Not even the April 1915 sinking of the Lusitania (for which the Germans apologized) had moved Congress from its isolationist position.
“Oh Lord! Oh Lord!” Wilson allegedly said when shown a copy of the telegram. He had just won his second term in office by the narrowest margin of any 20th-century election on his isolationist platform. Shortly after his January inauguration, Wilson had told Congress, “There will be no war.” But the Zimmermann telegram threatened to soften this conviction.
The telegram opened with the unpleasant news that the Germans intended to return to “unrestricted submarine warfare” even as they sought to keep the U.S. neutral. “In the event the policy of keeping America neutral does not succeed,” the telegram continued, “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.”
Zimmermann went on to explain that the ambassador should discuss this offer “most secretly” with the president of Mexico, then “add the suggestion that” the president “should, on his own initiative, invite Japan to immediate adherence and at the same time mediate between Japan and ourselves.” The Zimmermann note concluded by asking that the ambassador call the Mexican 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.”
Thomas Hohler, a British diplomat in Washington, D.C., had become used to Wilson’s waffling on providing support for Britain. “He’s the most agile pussy-footer ever made, and when any serious decision is taken, always tries to unload the responsibility on to someone else, and has been doing so this time again,” the diplomat reported. “But it does seem as if the Huns had fairly driven him into a corner out of which he can’t possibly wriggle!”
On March 1, a month after the commencement of unrestricted submarine warfare, Wilson released a translation of the telegram to the Associated Press. (At the request of the British government, he didn’t say how he’d come into possession of it.) As anticipated, the news made banner headlines and elicited outrage—along with considerable skepticism about the telegram’s authenticity.
Conspiracy theories abounded. George Sylvester Viereck, the editor of the New York weekly Viereck’s, called the telegram “an impudent hoax” that “reads like a dime novel.” “The alleged letter of Arthur Zimmermann is obviously faked,” Viereck told The New York Times. “It is impossible to believe that the German Foreign Secretary would place his name under such a preposterous document.” Herman Metz, a former New York congressman, called the telegram “bunk.” Metz said, “There is nothing Teutonic about it,” and, agreeing with Viereck, insisted that the German foreign minister would never “have signed such a note.” From The Saint Louis Amerika came the confirming assessment, “We have no hesitation declaring the supposed note of Zimmermann a forgery.” The New York Times summarized the views of the conspiracist camp as follows: “They credit the forgery to the English Government, which they saw consumed by the desire to force this country into war on the side of the Allies.”
Claims of forgery were so strong that Secretary of State Robert Lansing was compelled to submit to a Senate inquiry. Lansing assured the senators that the administration could guarantee that the “Zimmermann letter” was indeed genuine, but that it was necessary to keep the provenance unknown, because it would endanger those lives of the men who knew how the letter came into their hands.
But even to those who had inside information, the Zimmermann note was baffling. British Prime Minister David Lloyd George was awed by the “unwavering stupidity of Imperial German statesmanship.” Senator Claude A. Swanson of Virginia said that he had never seen “such a compound of knavery and idiocy.” The Japanese ambassador to Germany, blindsided by the plan, called it “too ridiculous for words.”
But the Zimmermann telegram was quite real. Mexico diplomatically declined what it was offering.
The German press appeared to share Zimmermann’s delusional ambitions. Vorwärts ran a headline anticipating the prospective “reapportionment of America” following the inevitable German-Mexican military victory over the United States. Vossische Zeitung expected Mexico’s government and its people to be tempted by the Zimmermann offer. “Given the mortal hatred of all Mexicans against America, it is certainly to be expected that with the outbreak of a German-American war Mexico will turn against the United States.”
At the same time, some did note the “mortifying embarrassment” that the telegram had caused in the German Foreign Office, especially after years of working judiciously to maintain American neutrality in the war. Others marveled that the Foreign Office could have been so heedless as to send such a sensitive communication via wireless, and expressed their bewilderment that a top-secret document could have ended up in American hands. Had the Americans cracked the German encryption codes? Had a courier been intercepted?
International-affairs analysts were perplexed at what one called the German Foreign Office’s “false assessment” that Mexico possessed the will, let alone the military capacity, to invade its northern neighbor. And the impact of the telegram’s leak was to dramatically change the complexion of U.S. foreign policy. “Until now the broad masses of Americans depended on the fact that the war was being fought far from America,” a writer for Vossische Zeitung noted. “Now they have realized that a battle can break out right on their own border.” What could Zimmermann and his colleagues have been thinking?
Zimmermann himself remained silent for a month as all this played out. Finally, on Tuesday, March 30, he spoke, appearing before the 600 delegates of the Reichstag to give his own account. He was as defiant and delusional as ever. Zimmermann denied that he had done anything wrong. He had issued “secret instructions” in coded language using an electronic conveyance that Zimmermann was certain “was absolutely secure.” He had not expected the contents of the cable to end up in the hands of the Americans.
Moreover, Zimmermann insisted that he had conducted diplomatic business appropriately: He had instructed an ambassador to enter into exploratory discussions with the president of a potential future ally. There had been no betrayal of trust with the Americans. The tone of his telegram was, in keeping with diplomatic protocol, “completely calm,” in no way incendiary. The telegram was merely an instruction to the ambassador to begin testing a partnership among potentially three nations—Germany, Mexico, and Japan—that would be built on Mexico’s “age-old and fully justified disinclination” toward the Americans.
If anyone was to be faulted, Zimmermann said, it was the Americans. They had turned a simple diplomatic exploratory query into an international incident. They had unleashed a “witch hunt” against Germany. They had acted shamelessly. The American president had refused to even speak with the German ambassador. If anyone had violated diplomatic trust and convention, it was the Americans.
Now, a month after the telegram’s public release, Zimmermann said, “calm and reasonable politicians like the great majority of the American people have now come to realize that there is nothing to object to the instructions we gave.” In his closing, Zimmermann conceded nothing. “I not only acted within my rights but performed my patriotic duty by doing what I did,” he said.
Less than a week later, on April 6, 1917, the U.S. declared war on Germany. It would be another four months to the day before Arthur Zimmermann stepped down as foreign minister.