Bundesarchiv, Bild 183-1988-0113-500 / CC-BY-SA
Much of the anti-German hysteria between 1914 and 1918 was fueled by the unfounded, yet popular, belief that the German government was spearheading extensive espionage activities in the U.S. The lack of actual evidence of these widespread efforts failed to ameliorate the suspicion centered on ethnic Germans and German nationals.
Although there was no spy network at the scale that was commonly believed, between 1914 and 1917, the German embassy in New York did handle activities that were intended to undermine the production of munitions to aid the Allied war effort. A small number of ambassadorial staff members were involved in these endeavors. Ambassador Johann von Bernstorff watched the political front, while Dr. Heinrich Albert, Germany’s Commercial Attache, supervised the spending of funds on espionage efforts, and Captain Franz von Papen, who later helped bring Adolf Hitler to power, was responsible for the actual activities of the spies and saboteurs.
In trying to keep the U.S. out of the war, a wide range of activities were pursued, including the failed efforts to dynamite the Welland Canal (to prevent the deployment of Canadian troops) and to destroy the Elephant-Butte Dam on the Rio Grande River. Plots against munitions production focused on either buying up or blowing up stock, and substantial funding went into the placing of bombs on steamers carrying war materials across the Atlantic. Many of the haphazardly constructed bombs failed to inflict any damage; however, other efforts were quite destructive, and by 1918, an estimated $150 million in damage had been carried out by sabotage agents in the U.S. The most costly and spectacular explosion took place in July 1916 on Black Tom Island, New Jersey. Here German saboteurs set off a series of explosions on the railroad wharves that resulted in the destruction of over 2 million pounds of munitions purchased by the Allied powers. The blasts could be heard almost 100 miles away, and in Manhattan and Brooklyn, thousands of heavy plate glass windows fell off of skyscrapers, terrifying local residents. Some efforts also resulted in a substantial loss of life. An explosion at a munitions plant in Eddystone, Pennsylvania, thought to be set by German agents, killed 112 workers, mostly women.
Although they did not involve actual physical destruction, other efforts pursued by the German embassy staff caused a major outcry. Plots to foment revolution in Ireland and India were motivated by a desire to cause turmoil in the British Empire and to compromise Britain’s battlefield effectiveness. The intercepted Zimmermann telegram, sent by the German Foreign Minister to the German Ambassador in Mexico, uncovered efforts to draw Mexico into the war on the side of Germany by promising the return of Texas, New Mexico, and Arizona, in the event that the U.S. entered the war on the side of the Allies and then lost the war. This news resulted in public opinion turning solidly against Germany.
The German espionage efforts ended, for the most part, in February 1917, when President Wilson severed diplomatic relations with Germany. However, most of the spies and saboteurs first fled to Mexico when the declaration of war was announced in April. There was no reason for them to continue their activities in the U.S., since the gamble for neutrality had been lost.