The wide spread use of mustard gas, chlorine, phosgene and tear gas in the First World War was one of the most horrible aspects of this truly horrible worldwide conflict. Although the Hague convention of 1899 already prohibited the use of chemical weapons, modern chemical weapons saw widespread use for the first time during this war, with 50,965 tons of chemical agents causing 1.3 million deaths through this period. Although this was one of the events that led to the general disapproval of chemical weapon use internationally, it is an often-overlooked aspect as it was also the start of trench warfare and part of the continued transition into an industrial warfare age.
Mustard Gas was a particularly horrible chemical weapon, not in its lethality but secondary infections from its effects, caused swelling in the eyes, horrible blisters, intense irritation to throat and chest, vomiting, and diarrhea, leaving troops vulnerable to attacks and illnesses. However many other deadlier gases were also in use in WW1, such as chlorine and phosgene and the horrors that these substances brought to the War led to the ban of their use by the 1925 Geneva Protocol. This treaty declared in its opening line that the “use in war of asphyxiating, poisonous, or other gases, and of all analogous liquids, materials, or devices, has been justly condemned” . However mustard gas continued to be used by Imperial Japan in the Second World War, and was stockpiled and used by Saddam Hussein against Kurds in the Iran-Iraq War. It has been made clear that setting international precedents isn’t enough to stop this sort of history repeating itself, instead these chapters of history should be used to educate and should be remembered, to keep the disgust in and condemnation of chemical weapons alive.