Chemical and biological weapons have been used since ancient times, and analyzing the employment of these weapons shows a pattern of use that has application today.
- There are indications that incendiary chemicals were used in Greece as early as 1200 B.C. Pitch, sulfur, resins, petroleum, and quicklime were forms of "Greek fire" at sea, when mariners threw containers of burning caustic chemicals into enemy ships. During the Peloponnesian Wars, the Spartans used clouds of poisonous sulfur dioxide in the siege of cities. Use of incendiary chemicals was based on wind direction; downwind, an enemy could not reciprocate.
- In 600 B.C. the Athenian Solon used hellebore root to contaminate a river that provided drinking water to a besieged city, causing its defenders to desert. The Athenians outside the city had access to and could poison the river; the defenders could not do the same to the Athenians.
- The famous Carthaginian Hannibal won a sea battle in 184 B.C. by having sailors throw earthen pots full of poisonous snakes and adders into Roman ships. When the Roman crews saw the wriggling serpents in their ships, such confusion set in that the fleet had to flee. Hannibal knew that the Romans had no such weapon with which to retaliate.
At the beginning of the 20th century, both biological and chemical warfare already had a long history, but World War I generally is regarded as the first large-scale use of chemicals in warfare. Fritz Haber, director of Germany's Kaiser Wilhelm Institute, developed chlorine gas as a weapon, then improved on it with phosgene and finally mustard gas, the most effective chemical agent used in World War I. Mustard produced eight times the casualties of all other German chemicals and no effective defense had been developed against it. Haber knew that the Allies did not have the industrial chemical capability to produce these agents and that it would take them a long time to build it.
On 22 April 1915, Haber signaled the release of his gas against French Colonial troops at Langemarke near Ypres in Flanders. As a sickly green cloud five feet high hugged the ground and moved toward their line, the French troops broke and ran amid screams of pain and panic. Later investigation showed 350 dead of 7,000 total casualties.
The world screamed foul and accused Germany of violating civilized conventions, but throughout history, chemical and biological warfare has been practiced despite laws intended to ban its use. Always the user has found justification or a legal loophole. In this case, the Germans were quick to point out that the 1874 Brussels declaration banned only the use of poison bullets, the 1891 Hague Gas Convention prohibited "the use of projectiles for the sole object of diffusion of asphyxiating or deleterious gases," and the Hague Conventions of 1899 and 1907 dealt with the use of projectiles for spreading poisonous gases—the release of gas from cylinders fixed in the ground did not violate any of these rules. In addition, many nations had not signed these early agreements and the status of these conventions as international law was questionable at best. Alfred Thayer Mahan, a member of the U.S. delegation to the 1899 Hague Convention, was among those who argued against the resolution, and the United States did not sign.
In spite of the public outcry, attempts to prohibit the use of chemical or biological weapons after World War I by treaty, protocol, and convention failed. Article V of the Washington Arms Conference of 1922 dealt with prohibitions of gas and bacteriological warfare, but the treaty never went into effect. The Geneva Protocol of 1925 also carried a provision that prohibited the first use of poison gas and bacteriological agents, but the restrictions ceased to be binding if an enemy used the weapons, and retaliation was authorized. This protocol was not approved by the United States until 50 years later, in 1975.
The use of chemical weapons continued, and the pattern remained consistent. Italy used mustard gas against Abyssinian troops in 1936, but not against the Allies in North Africa. Japan did the same against the Chinese in 1937, but not against the United States a few years later. What was the difference? The answer is that chemical warfare is employed when there is no chance of reciprocal use. It was safe for Italy and Japan to use mustard against the Abyssinians and Chinese, but the United States and her allies still had chemicals from World War I. Public opinion and international law had little effect.
Egypt used mustard in Yemen during the 1960s with no retaliation and very little outcry or objection from the rest of the world. Yemen did not have the capability to respond with chemical weapons.
Saddam Hussein used mustard gas against the Kurds in his own country, knowing that they could not get or use chemical weapons.
The Aum Shinrikyo cult used Sarin nerve gas in a 1995 terrorist attack against civilians on the Tokyo subway.
Chemical and biological weapons are employed when a user is convinced that his enemy cannot respond with a similar weapon. Fear of retaliation, not international law, has been the most successful deterrent. In spite of this, the most recent international agreements remove all chemical weapons from the arsenals of law-abiding countries. It used to be that chemical weapons could be produced but not used, except in response to use by an enemy, but the 1993 Chemical Weapons Convention Agreement took away this retaliation clause. Most major military powers had stockpiles of chemical weapons that they must eliminate.
The threat of retaliation no longer will stop an abuser because he will know that his victim cannot respond with similar weapons. The world has been stripped of the most effective control—deterrence—and now must pray that new treaties will be effective where old treaties failed.
Captain Landersman is employed by the Johns Hopkins University Applied Physics Laboratory as fleet representative on the staff of Commander, Naval Surface Force, U.S. Pacific Fleet, in San Diego, California.