chemical warfare

chemical warfare (CW) is usually understood to mean the employment of toxic materials such as mustard gas, nerve gas, and phosgene. The Italians used mustard gas in Abyssinia, but chemical weapons were not used during the Second World War, though the Japanese may have used them during the China incident. But smokescreens and flamethrowers, also technically part of CW, were widely employed by both sides.

Morality played little part in the reluctance of either side to use CW. As with biological warfare, fear of retaliation was a major factor, and the speed of modern warfare also militated against its use. Although CW was never used, chemical weapons were deployed (see Bari), and with the experience of the First World War behind them the European combatants of the Second were, by September 1939, well advanced in their defensive preparations against it. British gas protection, detection, and decontamination equipment were considered the best in the world, while anti-gas installations were part of the Maginot Line and of communal shelters in Paris. Germany and the USSR, too, were well prepared to take defensive measures, though in Germany there was a shortage of gas masks.

In September 1939 the only power in the northern hemisphere to have developed an offensive capability with the various gases they possessed was the USSR. The Germans had about 2,900 tons of CW gases, but no adequate means of delivering them as Hitler banned their offensive use. Nevertheless, the Germans did use toxic smoke during the siege of Sevastopol; and they were the first to begin the production of a nerve gas, Tabun, in 1942. Another, Sarin, was ready for production by the end of the war, by which time the still more lethal Soman was also under development.

At the height of the invasion scare in July 1940 the British had a mere 410 tons of gas. This was rapidly increased until by December 1941 they had stockpiled 15,262 tons of mustard, phosgene, and other gases which could be delivered by artillery shells or bombs, and this quantity had more than doubled by the end of the war. Apart from possibly using it against a German invasion in 1940 (see SEALION), the only other time Churchill seriously considered employing this stockpile, against German cities, was when the V-1 attacks on London started in June 1944 (see V-weapons). But the idea was vetoed by the Chiefs of Staff as impracticable.

The USA called its mortar units chemical warfare companies, a hangover from the First World War when mortars were used to lay down smoke or gas; but like the UK it was lacking in CW weapons when it entered the war. A joint agreement on their use was soon worked out with the UK, whereby their first use had to be agreed between the two powers, but either could retaliate without the other's permission. The Eighth US Army Air Force based in the UK was supplied by the British with 10,000 phosgene-filled bombs. But American production of CW weapons was quickly started and thirteen new plants were built for this purpose during the war. By 1945 the USA had stockpiled 87,000 tons of toxic chemicals, but a plan to use some of it against the Japanese on Iwo Jima was vetoed by Roosevelt who had twice publicly declared he would only use CW in retaliation.

Japan was the only combatant nation which may have employed CW, though Tōjō and other Japanese officials insisted that they had only used tear and sneezing gases. Documentary evidence to the contrary is lacking, but one report states that the Japanese had employed gas in the China Incident 876 times up to the end of June 1941. It was also alleged that in October 1941 Japanese aircraft dropped gas bombs on the suburbs of Ichang, the last navigable port on the River Yangtse, killing 600 Chinese soldiers. Once Japan was at war with the USA all offensive use of CW was stopped, for fear of retaliation, though Louis Allen relates that a German-invented gas bomb, filled with prussic acid, was employed by the Japanese against British armour during the Burma campaign (see Burma: The Longest War, London, 1984, p.301).

During the war employing chemicals against plants was regarded as part of biological warfare, though nowadays it would be regarded as part of CW. A chemical compound, isopropyl phenyl carbamate, was developed in the UK in 1942 which would destroy crops and another, calcium-2-methyl-chlorophenoxy-acetate, which would kill root crops. But Churchill decided not to manufacture either as they would take too long to produce in bulk. The data were given to the USA, which in mid-1945 considered spraying Japanese rice crops with ammonium thiocynate. See also scientists at war.

Bibliography

Harris, R., and and Paxman, J. , A Higher Form of Killing (London, 1982).