The tactical use of microorganisms and toxins as weapons has been attempted by many warring parties, including aboriginal Americans who tipped their arrows in amphibian-derived poisons. Fomites—entities that harbor and transmit disease—have been used to spread infection since antiquity. During the fourteenth century siege of Kaffa, a Genoese cathedral city on the Black Sea, the attacking Tatar force was struck by plague. They catapulted their diseased cadavers into the besieged city in an attempt to start an epidemic in 1347—or perhaps to trigger a collapse of morale within the city walls. An outbreak of plague did ensue and Kaffa fell. Ships carrying refugees from Kaffa are thought to have begun the second plague pandemic in Europe.
Smallpox was deployed as a weapon against Native Americans by the British in the eighteenth century.10 During the French and Indian War, Sir Jeffrey Amherst proposed the use of this weapon in order to reduce the tribes hostile to the British. When smallpox broke out at Fort Pitt in 1763, a Captain Ecuyer gave blankets and a handkerchief from the smallpox hospital to Indians and recorded in his journal, “I hope it will have the desired effect.” A smallpox epidemic did follow, although it is impossible to isolate the cause.11
The formulation of Koch's postulates12 and the development of modern microbiology in the nineteenth century led to the isolation and production of specific pathogens. In the ensuing years, many states attempted to develop pathogens and weaponize them. In World War I, Germany pursued an ambitious program using attacks on livestock in neutral countries and poisoning animal feed for export.
Japan conducted biological warfare research from 1932 onwards in occupied Manchuria. Prisoners were injected with anthrax, meningitis, cholera, and plague. At least 10,000 are said to have died. Eleven Chinese cities were attacked using contaminated water and food supplies. Pathogen cultures were also sprayed from airplanes. Plague was developed by allowing laboratory fleas to feed on plague-infected rats; these fleas were then harvested and were released by aircraft over Chinese cities. Fifteen million fleas are reported to have been released per attack.
During the same period, the British experimented with weaponized anthrax off the coast of Scotland. It was the discovery of the Japanese program at the end of World War II, however, that galvanized research in the United Kingdom, the United States, and the USSR. Japanese scientists were granted immunity from war crimes prosecution in exchange for extensive debriefings. During the Korean War the U.S. program expanded, and full-scale production of pathogens for weapons began in 1954. As part of a biological countermeasures program, American cities like New York and San Francisco were surreptitiously used as laboratories to test aerosolization. The offensive program was unilaterally terminated by President Nixon in 1969, and in 1975 the United States ratified the Biological and Toxic Weapons Convention. This treaty prohibits the development, production, and retention of microbial or other biological stockpiles in quantities that have no justification for prophylactic purposes.
Unlike the Chemical Weapons Convention, however, the Biological and Toxic Weapons Convention has no provisions for verifying compliance. It is now widely conceded that several signatories have violated the Convention's provisions. For example, the KGB weaponized the lethal toxin ricin by producing small metallic pellets that were cross-drilled, filled with the poison, then sealed with wax that would melt at body temperature. The pellets were discharged by a spring-loaded weapon disguised as an umbrella. By this means the Bulgarian dissident Georgi Markov was assassinated in London in 1978 and at least six other persons were murdered. In 1992 President Yeltsin disclosed that the Soviet Union had pursued its biological warfare program in violation of the Convention and confirmed that an outbreak of anthrax in 1979 had been caused by an accidental release of spores from a biological weapons facility.
The scope of the Soviet program, as described by a defector, 13 embraced more than 55,000 scientists and technicians. Yeltsin promised to suspend these activities; a 1995 report, however, concluded that between 25,000 and 30,000 persons were still engaged in various related programs.
The Iraqi program, while on a different scale, is known to have been extensive, and may have produced up to ten billion doses of anthrax, botu-linum toxin, and aflatoxin. UNSCOM, the UN agency set up after the Gulf War to discover and dismantle Iraq's programs of weapons of mass destruction, concluded that biological agents had been weaponized in considerable variety, including 155 mm artillery shells, 122 mm rockets, aircraft bombs, missile warheads, and aerosol tanks. UNSCOM was unable to determine, however, whether these weapons had been destroyed.
Today, it is thought that China, Egypt, Iran, Libya, Taiwan, Israel, and North Korea have active biological weapons programs.14 Public sources have estimated that between 10 and 25 countries possess or are seeking biological weapons. Unlike nuclear and chemical weapons, biological agents are easy to make and conceal and they are inexpensive. They can be produced in facilities that are also involved in legitimate scientific and pharmaceutical activities. These programs can flourish despite rigorous export control regulations because the same agents that furnish lethal weapons are also naturally occurring microorganisms and toxins. Similarly, the dual nature of biological agents makes verification of treaty commitments against weaponizing these agents virtually impossible. Finally, the advanced nature of the Soviet program and the temptation to market its fruits to other states presents a scenario every bit as disturbing as that involving Russian nuclear devices.
This duality of use—biology as medical science/war weapon—that so bedevils control regimes also, however, holds the possibility for at least tempering the problem. The Soviet program turns out to be readily convertible to peaceful uses, in a way that its nuclear weapons program is not. One commentator has asserted that many of the Russian biological weapons facilities can be readily converted to biomedical research work and vaccine production, providing employment to a large number of scientists and technicians.15 In a highly creative approach, another commentator has argued that trade regimes and nonproliferation regimes can be carefully crafted in order to attract and enmesh a new tier of states that have been recently endowed with advanced technological capabilities, including the capacity to manufacture weapons of mass destruction.16 This approach plays on the new market-state and its intertwining of security and commercial links among states such that the transparency so crucial for market development can also be used to prevent clandestine military development.
At present, however, it is hard to get security analysts to pay much attention to biological weapons. To persuade them to pay more, we must first answer the question: if these weapons are so easy to deploy and so lethal, 17 why haven't we seen more of their use?*
The two sets of consumers for such weapons are military commanders and terrorists. For commanders, biological weapons are too slow to affect operations at the front (it may take days or weeks for an enemy soldier to sicken, during which he can do a lot of damage) and too unpredictable18 (because the wide diffusion of virulent agents can infect one's own troops).† For terrorists, the same features of biological weapons cut the other way: delay allows perpetrators time for escape, and an agent like smallpox is terrifying to the public because it is unpredictable owing to the fact that it is communicable. Communicability poses its own threats, however; it may be some time before the terrorists know whether they are themselves infected and are infecting others (their colleagues, for example) unintentionally. Accordingly, many biological weapons programs have mainly focused on anthrax spores that enter the lungs and hatch bacteria that multiply rapidly within the body but don't infect anyone else.
Genetic engineering, however, may be able to make biological weapons far more useful to both the commander and the terrorist. It should be possible to design a virus that would disproportionately afflict members of a particular ethnic group, giving safety to attackers from a different group.19 Genetic engineering could also match a particular virus with an effective vaccine so that the aggressor would be immunized; or piggyback two agents, one quick and confined and the other latent and communicable. This sort of engineering will allow for the cloning of vast quantities of both traditional pathogens and new designer agents; these could be created quickly and cheaply, while their antidotes might take decades to develop. Such frightening prospects also hold within them some hope: the revolu-tion in genetics might also provide framework vaccines and antidotes that can be quickly modified and rapidly produced.
If biological weapons were used today against a civilian population, the public health systems of any of the major countries would be quickly overwhelmed. Our best strategy lies in recognizing the new and distinct nature of this threat and strengthening the public health surveillance systems,* as well as the intelligence collection capabilities, that can quickly detect and possibly thwart such attacks.