This Leavenworth Paper chronicles the introduction of chemical agents in World War I, the U.S. Army's tentative preparations for gas warfare prior to and after American entry into the war, and the AEF experience with gas on the Western Front. Chemical warfare affected tactics and almost changed the outcome of World War I. The overwhelming success of the first use of gas caught both sides by surprise. Fortunately, the pace of hostilities permitted the Allies to develop a suitable defense to German gas attacks and eventually to field a considerable offensive chemical capability. Nonetheless, from the introduction of chemical warfare in early 1915 until Armistice Day in November, 1918, the Allies were usually one step behind their German counterparts in the development of gas doctrine and the employment of gas tactics and procedures. In his final report to Congress on World War I, General John J. Pershing expressed the sentiment of contemporary senior officers when he said, "Whether or not gas will be employed in future wars is a matter of conjecture, but the effect is so deadly to the unprepared that we can never afford to neglect the question." General Pershing was the last American field commander actually to confront chemical agents on the battlefield. Today, in light of a significant Soviet chemical threat and solid evidence of chemical warfare in Southeast and Southwest Asia, it is by no means certain he will retain that distinction. Over 50 percent of the Total Army's Chemical Corps assets are located within the United States Army Reserve. This Leavenworth Paper was prepared by the USAA Staff Officer serving with the Combat Studies Institute, USACGSC, after a number of requests from USAA Chemical Corps officers for a historical study on the nature of chemical warfare in World War I. Despite originally being published in 1984, this Leavenworth Paper also meets the needs of the Total Army in its preparations to fight, if necessary, on a battlefield where chemical agents might be employed.

This explosive look into the dawn of chemical warfare during World War I is "a terrifying piece of history that almost no one knows" (Hampton Sides). In 1915, when German forces executed the first successful gas attack of World War I, the world watched in horror as the boundaries of warfare were forever changed. Cries of barbarianism rang throughout Europe, yet Allied nations immediately jumped into the fray, kickstarting an arms race that would redefine a war already steeped in unimaginable horror. Largely forgotten in the confines of history, the development of the U.S. Chemical Warfare Service in 1917 left an indelible imprint on World War I. This small yet powerful division, along with the burgeoning Bureau of Mines, assembled research and military unites devoted solely to chemical weaponry, outfitting regiments with hastily made gas-resistant uniforms and recruiting scientists and engineers from around the world into the fight. As the threat of new gases and more destructive chemicals grew stronger, the chemists' secret work in the laboratories transformed into an explosive fusion of steel, science, and gas on the battlefield. Drawing from years of research, Theo Emery brilliantly shows how World War I quickly spiraled into a chemists' war, one led by the companies of young American engineers-turned-soldiers who would soon become known as the "Hellfire Boys." As gas attacks began to mark the heaviest and most devastating battles, these brave and brilliant men were on the front lines, racing against the clock -- and the Germans -- to protect, develop, and unleash the latest weapons of mass destruction.

In Behind the Gas Mask, Thomas Faith offers an institutional history of the Chemical Warfare Service, the department tasked with improving the Army's ability to use and defend against chemical weapons during and after World War One. Taking the CWS's story from the trenches to peacetime, he explores how the CWS's work on chemical warfare continued through the 1920s despite deep opposition to the weapons in both military and civilian circles. As Faith shows, the believers in chemical weapons staffing the CWS allied with supporters in the military, government, and private industry to lobby to add chemical warfare to the country's permanent arsenal. Their argument: poison gas represented an advanced and even humane tool in modern war, while its applications for pest control and crowd control made a chemical capacity relevant in peacetime. But conflict with those aligned against chemical warfare forced the CWS to fight for its institutional life--and ultimately led to the U.S. military's rejection of battlefield chemical weapons.

This book is open access under a CC BY-NC 2.5 license. On April 22, 1915, the German military released 150 tons of chlorine gas at Ypres, Belgium. Carried by a long-awaited wind, the chlorine cloud passed within a few minutes through the British and French trenches, leaving behind at least 1,000 dead and 4,000 injured. This chemical attack, which amounted to the first use of a weapon of mass destruction, marks a turning point in world history. The preparation as well as the execution of the gas attack was orchestrated by Fritz Haber, the director of the Kaiser Wilhelm Institute for Physical Chemistry and Electrochemistry in Berlin-Dahlem. During World War I, Haber transformed his research institute into a center for the development of chemical weapons (and of the means of protection against them). Bretislav Friedrich and Martin Wolf (Fritz Haber Institute of the Max Planck Society, the successor institution of Haber’s institute) together with Dieter Hoffmann, Jürgen Renn, and Florian Schmaltz (Max Planck Institute for the History of Science) organized an international symposium to commemorate the centenary of the infamous chemical attack. The symposium examined crucial facets of chemical warfare from the first research on and deployment of chemical weapons in WWI to the development and use of chemical warfare during the century hence. The focus was on scientific, ethical, legal, and political issues of chemical weapons research and deployment — including the issue of dual use — as well as the ongoing effort to control the possession of chemical weapons and to ultimately achieve their elimination. The volume consists of papers presented at the symposium and supplemented by additional articles that together cover key aspects of chemical warfare from 22 April 1915 until the summer of 2015.