International Law and the Problem of Modern Armaments, 1860s–1970s

When the Declaration of St. Petersburg prohibited small-caliber explosive bullets in 1868, other, non-explosive bullets rivaled their destructive power. Likewise, the prohibition of expanding bullets in 1899 was soon overtaken by new bullet designs. And even the Geneva Gas Protocol, which outlawed the use of chemical weapons in 1925, was surpassed by events when future urban warfare was waged using incendiary bombs rather than aerial chemical weapons. Learning from the past, the next prohibition of a particular weapon to be codified under international law–the Biological Weapons Convention–included provisions on the development of new biological weapons.

This paper charts the history of weapons prohibitions under international law from the 1860s to the 1970s. Focusing on codified prohibitions, the paper argues that this body of law has been afflicted by the persistent challenge of keeping up with fast–and accelerating–technological change in the weapons sector.

By offering an integrated analysis of international law and weapons technology, the paper contributes to the historical scholarship on the laws of war. The key question in this literature continues to be the relationship between law and wartime violence; whether law reduces violence in war or whether by codifying violence, law legitimizes war. Weapons prohibitions have been widely dismissed in this scholarship as they tend to focus on marginal technologies rather than those most commonly used in combat by major military powers. But this misses the influence this project did have on conceptions and practices of wartime violence. Even as technology outpaced law, the moral expectations raised by the law continued to reverberate in subsequent wars.

This paper draws on research in the archives of the League of Nations and the International Committee of the Red Cross as well as national and university archives in the UK, US, and Germany.