The Zimmermann Telegram

In 1917, Europe, along with swaths of Asia and parts of Africa, were three years in to tearing themselves apart due to a confluence of technology, destruction, and outdated tactics known to us as the First World War. The Central Powers, made up of the German Empire, the Ottoman Empire, the Austro-Hungarian Empire, and Bulgaria were battling the Allied Powers, made up of The French Republic, Italy, The British Empire, Japan, and The Russian Empire. Noticeably absent and “neutral” was the United States. I put neutral in quotes there because the U.S. was anything but. America shipped war material, ammunition, and other supplies to the Allies but due to a large German immigrant population and a population with an intense isolationist worldview, remained on the sidelines. This all changed in 1917, while the U.S. had run ins and near conflicts with the Central Powers due to Germany’s policy of unrestricted submarine warfare on Trans-Atlantic shipping, it was a telegram sent to the German ambassador to Mexico, by the German Secretary of State that pushed America to the Allies. The telegram, intercepted and decrypted by the British, and turned over to the Americans, coupled with German submarine sinking of American vessels, brought the United States into the conflict on the side of the Allied Powers, tipping the scales decidedly into the Allies’ favor. This article is about that telegram and how it was a major factor in the loss of the war for the Central Powers.

To understand why it took the Americans three years to enter the war, we must first understand the reasons for staying neutral. First, while most Americans had cultural sympathies or full ties to Britain, France, and the rest of the Allied Powers, the U.S. had 10% of its population who ethnically identified as German. These Americans, for obvious reasons, did not want their adopted country to declare war on the land of their birth or their ancestral home, and for the first couple years of the war, the wider population of the United States agreed. Second, the American people saw WW1 as a strictly European affair and felt that it should stay that way. They believed it was folly to involve American soldiers in a war across the ocean that did not directly affect the American sphere of influence. Lastly, the United States was profiting immensely off the war, from an industrial and agricultural standpoint. Owing to the destruction or a shift to full war production of European industrial capability, military mobilization of the European population away from their places of employment, and blockades, the demand for American goods and food soared. However, in 1915, the sinking of the passenger ship Lusitania, killing 1,200 people, 128 of which were Americans, started a public opinion shift toward American intervention on the side of the Allies. For those unfamiliar, Germany pursued a policy of total war in the Atlantic Ocean, sinking both merchant and passenger vessels alike, in order to starve out the allies and curb their ability to wage war. So sharp was the outrage over the sinking of the Lusitania, that the Germans temporarily backed off their policy of unrestricted submarine warfare.

In 1917, a major political event occurred, turning the war toward a Central Power victory - the Russian Communist Revolution. The revolution took the Russian Empire out of the war and turned a two-front war, into a one front conflict. This freed up large numbers of Central Power soldiers to be rerouted to the western front, causing the war to start a swing against the Allies. To maximize further on this shift, Germany resumed its policy of unrestricted submarine warfare, causing more American losses, leading the United States to cut off diplomatic ties with Germany a few days after the policy resumed. Now enters our star, the Zimmermann telegram. The telegram was sent by Arthur Zimmermann, the Secretary of State/Foreign Secretary for the German Empire, to his ambassador in Mexico, essentially instructing the ambassador to propose a German-Mexican alliance, should the United States enter the war. Weirdly, Zimmermann also proposed the Japanese to be in this alliance, even though they were already on the side of the Allies, and the likelihood of them switching sides was nil. In this alliance, Germany would provide financial and material support to the Mexicans to invade the U.S. and even offered to support Mexico’s annexation of the U.S. states of New Mexico, Arizona, and Texas. While the telegram was sent in a coded format, it was intercepted by the British rather quickly. This is because Britain had cut Germany’s ability to send cables without a third-party allowing usage of their undersea telegraph cables, forcing Germany to rely on Sweden and the United States to transmit messages to overseas German ambassadors (like the one stationed in Mexico). The version of the message that went via the Swedes went from Stockholm to Buenos Aires over British telegraph cables, on to Mexico via the United States. Due to the usage of these British undersea cables, the plucky Brits were able to intercept it.

However, even with the message decoded quickly, the British were put in a precarious position. First, they had to convince the United States it was genuine. This on paper should be easy, but the U.S. was wary of efforts by the Brits to bring them into the war. Second and probably more important to British Secret Intelligence, it would also reveal that they had the ability to decode secret German telegraph cables. Ultimately, and after much angst, they passed it along to their American counterparts and convinced them that it was a genuine message. Understandably, the American public, holding now anti-German sentiments due to the unrestricted submarine warfare policy, and more historically, anti-Mexican sentiments, were outraged.

The United States did not take the Zimmermann threat of a Mexican-German alliance as a militarily viable threat. The U.S. was in the very final days of the Pancho Villa expedition; a military invasion of Mexico to track down Mexican revolutionary figure, Pancho Villa, after he launched a boarder raid on U.S. territory (the last U.S. invasion in a series of military actions against Mexico that showed the U.S. was far stronger militarily than their southern neighbor). Additionally, Mexico was in the midst of a civil war and the current president, Venustiano Carranza, was not in a place logistically, militarily, or politically to mount such an action, although he did ask a military commission to assess the proposal, which they found to be unwinnable.

The ultimate consequence of the Zimmermann telegram was the slow defeat of the Central Powers in the First World War, ending in November 1918, due to the U.S. declaring war and siding with the Allies, following the admission of Arthur Zimmermann to the genuine nature of the telegram. At one point, following the U.S. entry into the war, 10,000 U.S. soldiers a day were arriving in Europe. Germany and the Central Powers couldn’t counter the U.S. surge of material and manpower, allowing the new combination of the United States, the British Empire, France, and the other Allies, to press home and defeat the Central Powers by the end of 1918.