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Chemical and Biological Weapons and Warfare

Chemical and Biological Weapons and Warfare. Chemical warfare is the military use of lethal, harassing, or incapacitating chemicals specifically designed to harm or to kill; biological warfare is the use of disease‐causing bacteria, viruses, rickettsia, or fungi; toxin warfare is the use of poisonous chemical substances naturally produced by living organisms, such as the highly lethal cobra toxin. These agents can be used to target humans, animals, and plants. The use of all such weapons has been condemned in customary and international law. Although allegations are numerous, confirmed or extensive use has been limited to a few conflicts in the twentieth century: notably World War I (1914–18), the Ethiopian‐Italian War (1935–36), and the IranIraq War (1980–88).

In World War I, lethal chemical warfare began on 22 April 1915 with the German release of chlorine gas at Ypres on the Flanders front. By the time U.S. troops entered combat, its technology was fully developed. New agents, notably phosgene (an asphyxiating agent) and mustard (a blister agent called a vesicant), had been developed and used. Cylinders, projectors, and shells were the means of delivery. Gas masks protected soldiers against asphyxiating agents, but no adequate protection had yet been found against mustard gas, which attacked the skin.

After the war, widespread revulsion against gas, combined with the fear that in future conflicts it would be used against civilian populations, led to attempts to ban it. Notable success came with the Geneva Protocol on chemical and bacteriological (1925), which prohibited the use in war of “asphyxiating, poisonous or other gases and of bacteriological methods of warfare.” Most major powers hedged their accession, reserving the right of retaliation, thereby rendering the Geneva Protocol a “no first use” treaty. In the United States, the ratification debate dramatized the division between proponents and opponents of chemical warfare. The proponents, led by Gen. Amos Fries, chief of the Chemical Warfare Service, argued that gas was a relatively humane weapon and that ratification of the Geneva Protocol would seriously affect national security. Their opponents argued that gas was an indiscriminate, immoral, and inhumane weapon. The national security argument prevailed in the Senate. The United States did not ratify the protocol until 1975.

During the opening phases of World War II, it was widely expected that chemical weapons would be used. The use of mustard gas by the Italian Air Force against Ethiopian soldiers and civilians was regarded as an anticipatory prelude to massive aerial gas attacks against Western cities. However, except for Japanese operations against the Chinese, gas was not used in combat during World War II. Most of the belligerents were initially unprepared to use it and reluctant to expose their civilian populations to a gas attack from the air. Strategic restraint dictated tactical restraint. President Franklin D. Roosevelt, who had an abhorrence for gas warfare, committed the United States to a policy of retaliation, throwing a deterrent shield around his more vulnerable allies. During the war, although it undertook a biological warfare program, the United States did not mass‐produce lethal antipersonnel agents.

The wisdom of Allied restraint was confirmed by the discovery in Germany (1945) of stocks of nerve gases (tabun, sarin, and soman), which kill by attacking the nervous system. These agents, far more lethal than any in the Allies' arsenal, went undetected by Allied intelligence during the course of the war. Chemical weapons now could be considered “weapons of mass destruction,” especially if the new agents were wedded to missiles. Moreover, the potential development of an operational capability for biological weapons posed an even greater threat to the security of the United States.

American policy in the postwar period was characterized by cyclical shifts determined largely by the political rhythms of the Cold War. In periods of confrontation, intensified by mutual suspicion, emphasis fell upon chemical and biological warfare preparedness. In periods of detente, emphasis fell upon the furthering of security through arms control and disarmament. These two trends, however, were not mutually exclusive. From 1946 to the early 1950s, when the policy of retaliation only was being reexamined by government committees, American preparedness efforts lagged. In 1956, the National Security Council reversed its policy: in the future, the decision on chemical and biological weapons would be based on “military effectiveness.” During the Kennedy and Johnson administrations, funding increased significantly, reaching its maximum in fiscal year 1965: the nerve agents sarin and VX; mustard gas; irritant, incapacitating, and defoliant agents all were stockpiled, and approximately thirteen biological and toxin agents (including anthrax and botulin) were produced. The United States developed a multitude of delivery systems, ranging from multiple rocket launchers to missiles.

U.S. use of defoliants and riot control agents during the Vietnam War led to condemnation by the international community and by scientists who saw the use of these “nonlethal” agents as a contravention of the Geneva Protocol, posing a danger of escalation to the use of lethal agents. This political backlash, along with expert consensus that biological weapons capability was militarily unreliable and not essential to national security, led President Richard M. Nixon in 1969 to renounce that option and to order the destruction of the American stockpile. In 1970, he also ordered the destruction of toxin stocks. This unilateral renunciation of biological and toxin warfare by the United States spurred the completion of the 1972 Convention on the Prohibition of the Development, Production and Stockpiling of Bacteriological (Biological) and Toxin Weapons (BTWC), which entered into force in 1975.

The period of detente that characterized the Nixon and Carter administrations was ended by the Soviet invasion of Afghanistan (1979). Subsequently, the United States charged that the Soviet Union operated a biological weapons facility at Sverdlovsk in violation of the BTWC, and that Communist forces were waging chemical and biological warfare in Kampuchea, Laos, and Afghanistan: the so‐called Yellow Rain allegations, which centered on the aerial dispersion of tricothecenes—fungal toxin agents. These allegations were hotly debated. Matthew Meselson and other leading scientists argued convincingly that the government had mistaken bee feces for toxin agents. However, alarmed by the possibility that the Soviet Union was contemplating the development of new biological agents through genetic engineering, and convinced that the Soviets enjoyed overwhelming superiority in chemical weapons, the administration secured additional funding for defensive research, which rose steeply in the 1980s, peaking in fiscal year 1985, and won congressional approval in 1985 for a new binary chemical weapons production program. (Binary munitions, which are far safer to store than unitary munitions, combine two chemicals that mix upon firing.)

The second Reagan administration and the Bush administration saw a return toward disarmament. The thaw in Soviet‐American relations, concern on both sides regarding the dangers of proliferation, accentuated by the use of chemical weapons in the Iran‐Iraq War, led to bilateral agreements between the United States and the USSR on the mutual reduction of chemical weapons stockpiles. Multinational negotiations in the Conference on Disarmament led to the conclusion in 1992 of the Chemical Weapons Convention, which, unlike the Biological and Toxin Convention, contained strict provisions for verification and challenge inspections. The convention entered into force in 1997; it has been ratified by the United States and Russia.

Across these favorable developments in arms control and disarmament falls the shadow of the Persian Gulf War (1991). The war was preceded by fears, fueled by the precedent of the Iran‐Iraq War, that the Iraqis would use chemical agents against Coalition forces. Those fears were not realized. The stern American warnings to the regime about the consequences of such use, the folly of using these weapons against nuclear‐armed powers, and the blitzkrieg conduct of the coalition land operations militated against their use. The defeat of Iraq by Coalition forces, led by the United States, and the subsequent investigation of Iraq's facilities and capabilities by the UN Special Commission, revealed the extensive nature of Iraq's biological and chemical weapons programs, highlighting the continuing dangers of proliferation.

Despite the elimination of Iraq's weapons of mass destruction and the completion of the Chemical Weapons Convention, major problems remain in implementing any regime banning chemical and biological warfare: intelligence and verification, proliferation, terrorism, destruction, deterrence, and enforcement. If the Chemical Weapons Convention is successfully implemented, intelligence problems will be eased; however, the Biological and Toxin Convention, despite recent efforts to strengthen it, is still based on trust, and the task of verifying compliance, given the number of laboratories throughout the world, remains formidable. The list of potential proliferators in the Third World stands at approximately fifteen. The use of sarin in the Tokyo subway by the Aum Shinrikyo terrorists (1995) highlighted the vulnerability of modern societies to state‐sponsored or cult terrorism. The destruction of chemical agents is proving difficult, especially in Russia, because of its cost and environmental concerns. A new Chemical Weapons Convention, prohibiting the production, storage, and use of poison gas, and providing for monitoring of the civilian chemical industry with systematic and surprise inspections was signed by President George Bush in January 1993 after ten years of negotiations. Pressed by President Bill Clinton and Senate Majority Leader Trent Lott (R.‐Miss.), the U.S. Senate overrode concerns from the chemical industry and conservatives worried about North Korea, Iran, Iraq, and Syria, and ratified the treaty 74–26 on 24 April 1997. With seventy‐five nations approving the treaty it went into effect on 29 April 1997. By adhering to the Chemical Weapons Convention, the parties to the treaty are renouncing retaliation in kind. Deterrence therefore will depend upon the threat to punish violators by other means—nuclear or conventional. Relying on the former will threaten the developing structure of nuclear arms control. Finally, no treaty is stronger than the willingness of its adherents to enforce it.
[See also Arms Control and Disarmament; Nonproliferation of Nuclear Weapons, Treaty on the; Terrorism and Counterterrorism; Toxic Agents: Chemical Weapons Exposure; Toxic Agents: Agent Orange Exposure.]


Frederic J. Brown , Chemical Warfare: A Study in Restraints, 1968. Stockholm International Peace Research Institute, The Problem of Chemical and Biological Warfare: A Study of the Historical, Technical, Military, Legal and Political Aspects of CBW, and Possible Disarmament Measures, 6 vols., 1971–75.
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Erhard Geissler, ed., Biological and Toxin Weapons Today, 1986.
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Richard M. Price , The Chemical Weapons Taboo, 1997.

John Ellis van Courtland Moon

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Soman (or "GD") is a synthetic (human-made) compound that affects the functioning of nerves. As such, Soman is one of a group of chemicals that are known as nerve agents.

Soman was developed in Germany in 1944. Its original purpose was as an insecticide. The chemical, which does not occur naturally in the environment, is similar to the group of insect poisons (pesticides) called organophosphates, both in activity and in how they are applied (i.e., airborne release). However, Soman (and nerve agents in general) are much more potent and deadly than the insect nerve poisons.

Several properties of Soman are responsible for its potency. It is normally a clear, colorless, and tasteless liquid, and so is not easily detected. While it typically has a slight odor reminiscent of rotting fruit, this smell can be disguised upon mixing with water or food. Even wetting the skin with soman-contaminated water can be lethal, as the poison is absorbed through the skin. In addition, Soman can vaporize when heated, and retains its toxicity when inhaled. The vapor can even cling to clothing and affect others as is it released from the clothing.

The effects of Soman begin almost immediately upon exposure. Within minutes to hours the nerves that control the functioning of muscles are inhibited from turning off the stimuli that trigger muscle activity. At the molecular level, this occurs via the inactivation of an enzyme that breaks apart another chemical that acts as a bridge between adjacent nerve cells, and so allows a nerve impulse to flow. Because the bridging chemical remains intact, nerve impulses cannot be controlled or turned off. As a result of the constant activity, muscles such as the lungs tire and can cease to function. Some of the symptoms associated with Soman exposure include watery and painful eyes, coughing, rapid breathing, diarrhea, confusion, headache, slow or fast heart rate, and, in severe cases, unconsciousness, convulsions, and respiratory failure.

These effects occur for only a short time after Soman vapor is released into the atmosphere, since it is a very volatile compound. When incorporated into water or food, however, Soman can remain active and deadly for a longer time.

The damage due to Soman is cumulative. Because the chemical can persist in the body, repeated exposure increases the concentration of Soman in the body. People in low-lying areas and valleys can be especially susceptible, as Soman is more dense than air and so "settles out" near the bottom of depressions.

Soman was one of the nerve agents that may have been used against the people of Iran by the government of Iraq under Suddam Hussein during the Iran-Iraq war in the 1980s. Soman once also once produced as a chemical weapon by the United States. Production by the United States ceased decades ago.



Government of the United States. 21st Century Complete Guide to Chemical Weapons and Chemical TerrorismU.S. Demilitarization Program, Stockpile Destruction Emergency Plans, Nerve Gas and Blister Agent Civilian Treatement and First Aid, Home Sheltering Plans. Washington, DC: Progressive Management, 2002.


Agency for Toxic Substances and Disease Registry. "Nerve Agents (GA, GB, GD, VX)." Division of Toxicology, Centers for Disease Control and Prevention. March 13, 2003. <> (April 10, 2003).

Agency for Toxic Substances and Disease Registry. "Facts about Soman." Division of Toxicology, Centers for Disease Control and Prevention. March 12, 2003. <>(April 10,2003).


Chemical Warfare
Mustard Gas
Sarin Gas

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soman, colorless liquid used as a nerve gas. It boils at 167°C, evolving an odorless vapor. It is rapidly absorbed through the skin; death may result within 15 min of exposure. In nonfatal concentrations it is hazardous to the eyes. Soman is more powerful than tabun, acting faster and at lower concentrations. Chemically, soman is fluoromethylpinacolyloxyphosphine oxide.

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