1. For some of the scholarship on the history of biological and chemical warfare see SIPRI (ed.) (1971) The Problem of Chemical and Biological Warfare, vol. 1 (Stockholm: Almqvist & Wiksell; New York: Humanities Press); R. Harris and J. Paxman (1982) A Higher Form of Killing. The Secret Story of Gas and Germ Warfare (London: Chatto & Windus); L.F. Haber (1986) The Poisonous Cloud. Chemical Warfare in the First World War (Oxford: Clarendon Press); D. Richter (1992) Chemical Soldiers. British Gas Warfare in World War I (London: Leo Cooper); R. Evans (2000) Gassed (Thirsk: House of Stratus); B. Balmer (2001) Britain and Biological Warfare. Expert Advice and Science Policy, 1930–65 (Basingstoke: Palgrave Macmillan); P. Hammond and G. Carter (2002) From Biological Warfare to Healthcare. Porton Down 1940–2000 (Basingstoke: Palgrave Macmillan); M. Wheelis, L. Rózsa and M. Dando (eds) (2006) Deadly Cultures. Biological Weapons since 1945 (Cambridge, MA, London: Harvard University Press); J.B. Tucker (2006) War of Nerves. Chemical Warfare from World War I to Al-Qaeda (New York: Pantheon Books); U. Schmidt (2006) ‘Cold War at Porton Down: Informed Consent in Britain’s Biological and Chemical Warfare Experiments’, Cambridge Quarterly for Healthcare Ethics, 15(4), pp. 366–80; U. Schmidt and A. Frewer (eds) (2007) History and Theory of Human Experimentation. The Declaration of Helsinki and Modern Medical Ethics (Frankfurt am Main/New York: Franz Steiner); E. Spiers (2010) A History of Chemical and Biological Weapons (London: Reaktion Books). The article is part of a Wellcome Trust-funded project on ‘Cold War at Porton Down: Medical Ethics and the Legal Dimension of Britain’s Biological and Chemical Warfare Programme, 1945–1989’. I am grateful to the Wellcome Trust for its support. The relationship between the events in 1915 and the wider Just War Theories will be addressed in the later part of the essay.
2. M. Szöllösi-Janze (ed.) (1998) Science in the Third Reich (Oxford/New York: Berg), p. 318.
3. B. Sheppard (2000) A War of Nerves (London: Jonathan Cape), p. 63; see also P. Lerner (2003) Hysterical Men. War, Psychiatry, and the Politics of Trauma in Germany, 1890–1930 (Ithaca/London: Cornell University Press).
4. J.M. Roberts (2001) Europe, 1880–1945 (London: Pearson Education), pp. 220–8; see also Tucker, War of Nerves, p. 9.
5. Tucker, War of Nerves, p. 11; J. Terraine (1992) White Heat. The New Warfare (London: Leo Cooper), pp. 155ff; also C.H. Foulkes (1934) “Gas!”. The Story of the Special Brigade (Edinburgh/London: William Blackwood & Sons Ltd), p. 31.