To be sure, there have been states that have crossed the line and used WMD.  There have also been military factions within a sovereign state that took it upon themselves to release WMD, or use a clandestine, non-state group to do its dirty work.  It is the proliferation of such weapons into the hands of these non-state, sub-national actors that most concerns the experts (Hoffman 1997).  The mindset of some terrorists is such that they are drawn to explosions like arsonists are drawn to fire, so nuclear weapons are their preferred choice.  Other terrorists may have a preference for chemical weapons because of their long-term incapacitating effect since lots of survivors tend to develop nerve and brain damage over time.  Still other terrorists may have a preference for biological weapons because of their stealthiness and delayed impact since they mimic the effect of natural disease outbreaks.  There is a need for more scholarly research on this topic as no one really knows who will use what, when, and where (despite Tom Clancy's novels which usually involve a convention or sports venue).       

    Chemical (gas) weapons have a long history.  The most well-known incident involved the Japanese cult group, Aum Shin Rikyo (Supreme Truth) who released fatal sarin gas on the Tokyo subway system in 1995.  Toxic gases were also detected by Czech and Coalition troops during the First Gulf War.  At least 25 nations possess complete CBR capability, and 44 nations are suspected of being in the process of obtaining such capability.  The first chemical weapon used in battle was chlorine gas, which burns and destroys lung tissue, is easily made from common table salt, and is desirable to use on the battlefield because the big gas cloud usually wipes out an overpowering enemy.  Modern chemical weapons greater killing power (such as VX nerve toxin), and a lot less of it is needed to kill vast numbers of people.  Despite improvements in protective gear, there really is no good way to protect people from a large-scale chemical attack.

    Biological (germ) weapons were used in 1984 by a religious cult group in Oregon known as the Rajneeshees, who tried to win a local election by sickening local townspeople with a strain of salmonella sprayed on the salad bars in local restaurants.  The Bulgarian and South African governments have been known to use biological materials to kill political opponents, and the 2004 Ukrainian election involved allegations of poisoning.  Biological warfare agents were banned by the U.S. in 1969, but resurrected in 1990 under Project Clear Vision.  The oldest germs are the cheapest and most lethal -- anthrax, botulism, and the plague.   Bacillis anthracis (anthrax) has a 95% mortality rate, and can attack three ways -- cutaneous, intestinal, and respiratory.  The most well-known incident involving anthrax was the October 2001 case in which somebody mailed letters containing inhalation spores of anthrax to three news reporters and two U.S. Senators.  The germ, ebola, by contrast, only has a 70% mortality rate and smallpox 30%.  Anthrax spreads easily, although the secrets for powderizing it to military grade are classified at Ft. Detrick, the nation's biowarfare center.  It is believed that a freeze drying process is used to turn the spores into a powder, and then silica is added to remove any electrostatic charge, making it more dispersible.  One and a half to three microns in size is the most dangerous.  Designer powders are possible, which includes heavier powders that can be left on the ground to become airborne after awhile.  There is evidence that the Soviets were working on designer germs, which are created by mixing different kinds of viruses to mutate new organisms.  By far, however, the cheapest and easiest germ to produce is ricin, a toxic, incurable substance produced as a by-product from the processing of castor beans, which is an easily-found recipe on the Internet.  The mortality rate of ricin varies with the method of delivery.  The highest mortality results from injection of ricin under the skin, and Cold War-espionage stories abound with tales of spies who used assassination umbrellas that injected a pellet of ricin from their tips.  In 1993, Canadian authorities captured a neo-Nazi from Arkansas with a carload of ricin trying to cross the border.  In 1995, two Minnesota men associated with a tax-protest group called the Patriots Council were convicted of possessing ricin with intent to use.  In October 2003, someone hand-delivered a package containing Ricin to a mail-sorting center at a South Carolina airport, with a note complaining about federal rules mandating 10 hours of rest in every 24 for long-haul truckers.  The same person or group sent traces of Ricin to Senator Bill Frist's mail room in 2004.  Unlike anthrax, ricin is tough to aerosolize and inhale, the easiest way to deliver a fatal dose being injection or ingestion, and you need a lot for the latter.

    With nuclear weapons, most concern centers on the former Soviet Union, where so-called loose nukes or weapons-grade plutonium might slip out.  Russia is estimated to have some 20,000 warheads still assembled, and about 170 tons of plutonium and 900 tons of HEU (highly enriched uranium).  Treaties, such as the 1995 non-proliferation treaty which 182 nations signed, are regularly violated. CBR warfare requires intensive intelligence work on development, deployment, and delivery capabilities.  There is also concern over dirty bombs, technically called radiological dispersion devices, which use conventional explosives to fling radioactive isotopes in a plume of dust. The al Qaeda terrorist group is known to have made substantial efforts to buy black market isotopes. Plutonium and weapons-grade uranium are well secured, but that is not true of the lower-grade nuclear materials required for a dirty bomb.  Radioactive isotopes are commonly found. Hospitals and research universities have cesium, strontium, cobalt, and americium, and traces of americium are also in smoke detectors. Food processing plants, oil monitoring facilities, and other industries also have devices that use cobalt.  In addition, the U.S. is one of the world's worst offenders regarding nuclear waste.  There are currently about 45,000 tons of nuclear waste stored in 131 sites across the country, and by 2035, that amount is expected to grow to more than 115,000 tons.  Nuclear waste is usually in the form of spent fuel rods, and is highly radioactive and dangerous, and will be for tens of thousands of years.  Most expects advocate storing all of it under the Yucca Mountain in Nevada, but first shipments aren't scheduled to arrive there until 2010 at the earliest.  Launching nuclear waste into the sun isn't an option, not because it would hurt the sun, but because using Earth's biggest rocket, the Delta 4, would require about 3,000 trips, and the risk of rocket explosion in Earth's atmosphere would be too great.  The best way to "destroy" HEU is to blend it with proliferation-resistant low-enriched uranium (LEU).

Planning & Strategy
    The U.S. government has always had response plans in place in case of superterrorism, and there are several agencies and organizations involved.  FEMA (Federal Emergency Management Agency) has long (since 1992) administered the Federal Response Plan (FRP, or technically Public Law 93-288 - with additional copy of FRP at FindLaw, with Amendments since 1997 discussed at FAS).  Basically, the purpose of having an overall response plan is to more effectively enable the transition from crisis management (predominantly a law enforcement response) to consequence management (restoration of services in which the federal government helps out).  Let's take a look at this pre-9/11 planning showing some of the many agencies and departments (27 in all) involved in the overall response.

    The 2001-created Department of Homeland Security, and subsequent planning, has changed the look of this pre-9/11 planning.  Further input has come from the scenario/drill/exercises known as TOPOFF (Top Officials) which have been conducted since 2000.  TOPOFF exercises are "no notice" drills that last usually 5-7 days, and involve a fictional attack by a fictional terrorist organization.  The 2002 Bioterrorism legislation also has had an inpact, making billions of dollars available to upgrade local hospital and water systems, increasing the number of smallpox vaccines, making available potassium iodide tablets for radiation poisoning, and providing more money to the National Pharmaceutical Stockpile - secret stashes of medicine at locations throughout the United States.  The development of vaccines for each and every contingency is a current policy priority, but there is still the need to coordinate an overall response plan.

   Moving onto the topic of strategy, it should be noted that the U.S. has never ruled out the possibility of using nuclear weapons in retaliation for biological or chemical attack from a foreign source. This is not so much for deterrence as it is for reassurance. To understand this shift in strategic policy, one needs to understand the long-standing practice of nuclear deterrence, which was the basis of the Cold War. In the post-Cold War era, a strategy of preemption is ascendant, the reason being that the only sure way of disintegrating a stockpile of chemical and biological weapons about to be used is to nuke them.  Nuclear attacks on nuclear targets generally result in immediate destruction but the possibility of increased harm through radioactive debris fallout is great and must be controlled.  

    The basic idea of deterrence is to prevent attack by threatening retaliation. The military definition of deterrence involves a combination of magnitude and probability, which means a large stockpile of weapons and the willingness to use them in a system of layered precautions. The game of deterrence works best between two enemies who are about evenly matched, as in the Cold War between the U.S. and Soviet Union. Both of these nations regularly aimed about 2,000 nuclear weapons at each other for many years. This level of deterrent effect was overkill, as it would have destroyed both countries completely. On a practical level, all you would need for nations this size is about 700 nuclear weapons - which would destroy about 50% of the population and 65% of the economic infrastructure. These practical levels are known as plausible deterrent requirements.  Nuclear deterrence works best on the basis of overkill. 

    Efforts have been made to reduce the overkill capabilities of the U.S. and Soviet Union. The START treaties, for example, curtailed the use of multiple warheads, a prime contributor to overkill. When the Soviet Union broke up, the remaining central state only retained control over about 20% of the former nation's nuclear capacity. This meant that efforts had to be made to disarm or disable the remaining 80% of the former Soviet Union's capacity throughout all the various emerging states and former satellites. This has been accomplished mostly by disabling than by disarming. For example, the batteries have been removed from missile guidance systems or the explosive bolt charges have been removed from the covers of missile silos. Some 70% of the former Soviet Union's land-based nuclear capability has been disabled or is not being regularly maintained. We are currently in a START III phase which is aimed at curtailing nuclear submarine forces by 2010. Deterrence is not the same as preventing war; dismantling is not the same as eliminating war. 

CHEMICAL WEAPONS

    Chemical weapons are the most common type of CBR warfare. It's estimated that as much as a third of the world's arsenal consists of chemical weapons, so there's a lot of it stockpiled. Chemical warfare was first used by the British against the Kurds after the end of World War I (which was also a gas war). During the 1960's, a chemical war took place between Egypt and Yemen; during the 1970s, between Vietnam and Laos; during the 1980s, between Russian and Afghanistan; and in the 1990s, between Iraq and the U.S.  Many chemical wars have gone unnoticed or unreported.  

    Chemical weapons are classified by their effects: lethal, choking, hallucinogenic, etc. They are dispersed by different weapon systems. An exploding weapon system sprays the area with droplets, intended to contaminate clothing, implements, and terrain. A dispersion weapons system disperses into the air so finely, the chemical evaporates and is carried by the air to attack the respiratory system.  Doctors and nurses are working on procedures to handle chemical warfare casualties. The problem is acute since the agents get on clothing as well as flesh and is easily picked up by those treating the victims. To date, the most effective treatment for most forms of nerve gas is to get the soldier to inject him or herself with Atropine (by jabbing a syringe into a major muscle group, like the leg) soon after exposure. Atropine doesn't work with all agents, and you become quite sick if you inject it and haven't been exposed. Chemical weapons are better than biological ones because they're easier to calibrate and far less likely to spread out and harm friendly personnel.

BIOLOGICAL WEAPONS

    Biological warfare utilizes toxins, viruses, and bacterial agents. Toxin agents generally are broken down into two major groups: cytotoxins and neurotoxins (the only major military neurotoxins being the botulinum series).  Toxins work in one of two ways: postsynaptic and presynaptic. Postsynaptic toxins work by disrupting the nerve signals at synaptic junctions were nerve endings meet muscle. Presynaptic toxins work by accelerating the neural activity at synaptic junctions, and then stopping it completely. Despite minor differences in the agony of death, the effect is the same, complete muscular paralysis. Victims often drown in their own saliva. Some toxins can be engineered to effect only a certain part of the body, and these are called necrotic toxins. So-called "designer" toxins can make your limbs fall off, and others can affect only certain body organs.

    Virus agents infect the human body and work by multiplying or mutating, disrupting cellular activity and eventually killing the target by massive convulsions or hemorrhaging. Viruses used in warfare are militarily, bioengineered versions of naturally occurring strains. Viruses, as opposed to most bacteria, are immune from antibiotics.  Bacterial agents, however, can be grown to resist antibiotics.  Bacterial agents make up more than half the military biological agents (e.g., anthrax, salmonella, brucella, q-fever, cholera, and plague).

    Several nations have engaged in biological warfare even though prohibited by a pact signed in 1972. As a nation develops its biowarfare capability, there's usually a recognition that its use is counterproductive. There have been several "near misses" and accidents in nations' laboratories. The principle response to a biological attack is nuclear (a kind of spite from the grave strategy), and there's a lot of research into finding a more defensive way to survive. Biological warfare is too easy to start and too hard to stop. Terrorists who use it can expect severe retaliation. In 1979, a "meat packing" accident in Russia released an anthrax epidemic that killed over 1000 people. "Near misses" have also occurred in American facilities.

    Viruses are normally incubated from batches of existing strains found in preserved tissues of infected bodies, but others are synthesized from published accounts of a genome.  In 2002, for example, New Scientist magazine revealed that scientists created the first synthetic (man-made) polio virus, and the same technique could be used to create ebola or the 1918 flu strain. These particular viruses have short DNA key pair chains, and present technology allows short stretches of DNA to be custom-made.  One can also add key genes of a close relative. Ebola and smallpox replication, however, requires key viral proteins as well as the genome, but the ebola virus is only slightly larger than the polio virus. Smallpox has a rather lengthy chain, but its smaller cousins do not, such as mousepox or camelpox.  Anthrax, if it is synthesized, usually is a designer variant in the small DNA chain variety.

NUCLEAR WEAPONS

    There are two main type of nuclear weapons: fission (A-bombs) and fusion (H-bombs). Fission bombs were used on Japan in WWII. In fission bombs, a core of fissionable material is needed, usually plutonium-239 or uranium-235, both isotopes of regular plutonium and uranium. It is expensive and time-consuming to make these isotopes, which are found in about 1% of all regular plutonium and uranium. It takes a concentration of 20% of these isotopes to be classified as weapons-grade. Anything less can only be used for nuclear power reactors. HEU, or U-235 can be dissipated by mixing it with regular uranium, but there's no way to dissipate, dissolve, or dispose of weapons-grade plutonium. Enriched plutonium isotope is about 90% pure, and if you inject it into a nuclear reactor, it generates more plutonium.

    To make a bomb, a core of weapons-grade material is encased at just below critical mass (the point where chain reaction occurs). This means 20 pounds of plutonium or 40 pounds of enriched uranium (about the size of a football). A series of conventional charges are then placed around the casing to go off simultaneously so that the core implodes, rapidly compressing the core to start a chain reaction. Some types of fission bombs fire lumps of core material at another lump through tubular guns.  Fusion bombs use a primary fission reaction to trigger a secondary explosion. The fusionable material (usually a gas) goes "critical" and results in a secondary nuclear explosion. The combined two-stage explosion is 100 times more powerful than a fission explosion alone.

    An alternative to fission or fusion is a "dirty bomb" or radioactivity dispersal device, a conventional bomb wrapped in radioactive materials that disperse as fallout when the bomb explodes. Nuclear bombs can be made so small they fit inside a suitcase.  Low-yield nuclear bombs also exist, or what the U.S. military calls MOAB (mother of all bombs), and you can see a video of one by visiting DefenseLink.

    Incidents of nuclear smuggling rarely point to a particular buyer.  In 1995, however, German authorities uncovered a major ring of plutonium smugglers. It turned out the plutonium came from Russia. Russia has ten nuclear reactors each producing a half-ton of weapons-grade plutonium per year (enough for 100 missiles). Some Russian warheads ("Fat Boys") are missing or unaccounted for.  Also in the mid-1990s, more than 1,000 pounds of HEU -- enough material to allow terrorists to build more than 20 nuclear weapons -- sat unprotected in Kazakhstan. Recognizing the danger, the American government purchased the material and moved it to Oak Ridge, Tenn.  In October 2001, al Qaida claimed to have nuclear weapons, with expertise or material from Pakistan.  Part of the problem driving the mysterious internation smuggling market is the fact you can't just manufacture nuclear material and forget about it. These things require maintenance. Some of the radioactive material (like Tritium) will lose 5-6% of its power each year. The conventional explosives will degrade and become unstable and need to be replaced almost every year. The electronics must be tested regularly, and the batteries must be periodically replaced. Thousands of nuclear weapons are disassembled and reassembled (or discarded) every year.

    Estimates put the number of nuclear weapons in the world at about 55,000, with about 30,000 (7,000 deployed) belonging to the US and 25,000 (6,000 deployed) belonging to Russia. Deployed means the weapon is already mounted as a missile warhead and ready to launch. Britain and France have about 600 each. China has about 400 and the Israelis have at least 200. India and Pakistan are believed to have about 100 each, which is probably the same amount for overlooked South Africa.  North Korea probably has less than 100, and various Middle Eastern nations, most notably Iran and Iraq, probably have a smaller number in various stages of development.  There's enough nuclear weapons possessed by nations other than the US to shower every 100 square miles of the US with a nuclear blast.   Recent agreements would limit the United States and Russia to 1,700 to 2,200 nuclear warheads each by 2012, compared with about 6,000 the United States now has (in 2002) and about 5,500 held by Russia.

    Besides nuclear weapons, there are nuclear power plants to worry about. The Nuclear Regulatory Commission admits that plants are vulnerable to terrorist attack, and the FBI receives many threats a year against such plants.  Each plant has plans for a 50-mile "accident" zone, and each main reactor area is hardened with a containment dome.  Unfortunately, it's the waste cooling pools which are most vulnerable. These pools are stacked with thousands of pounds of waste fuel, and any loss of water would trigger an inextinguishable waste fire accompanied by a hydrogen explosion.  Waste pools are quickly becoming replaced by military-grade earth and gravel mounds.   

NATION STATE CAPABILITIES

    Few states admit they possess chemical weapons. Only the United States, Russia, Iraq, and India have admitted it. The United States, which has started to destroy its chemical weapons, has a stockpile of about 30,000 tons. Russia has declared 40,000 tons. Iraq, which acknowledged after the Gulf War that it had such weapons, claims that its chemical agents and munitions were destroyed during and after the war. India admits to having chemical weapons, but only for "defensive" purposes.  Dealing in chemical weapons has always been a back-alley business that nations have conducted in secret.  Typically, U.S. officials will point their finger at a list of "rogue nations." A 1992 DIA report concluded that Third World nations feel free to stockpile chemical weapons "without fear of repercussions from the international community."

Asia:   China, India, Pakistan, North Korea, and Taiwan have chemical weapons, and Burma wanted chemical weapons for domestic use. Vietnam captured large stocks of U.S. munitions at the end of the Vietnam War.  Al Qaidi terrorist groups in this region have always been interested in nuclear weapons.  North Korea: North Korea's stockpile of WMD is the largest in the Asian region.  North Korea has had chemical weapons since the 1960s, and sits on vast quantities of blister, blood, and nerve agents. The North Koreans have excellent delivery and dispersal systems, they constantly conduct WMD training exercises, and their civilian population is extensively trained in defensive measures.  Nobody knows their nuclear capability for sure.  South Korea: South Korea is suspected of having an extensive WMD program.  The South Koreans have the chemical industry infrastructure and technical know-how to produce sophisticated agents and designer weapons. Newspaper leaks from the 1980s have always cited a extensive chemical weapons program, but a 1986 U.S. Army Scientific and Technical Intelligence Bulletin reported little cause for concern. South Korea is regularly included in the annual list of nations proliferating weapons of mass destruction, but details are classified because the U.S. also stockpiles some of its own weapons in South Korea.  India: India has an extensive industrial infrastructure and the technical know-how to produce WMD. They are regular producers of the precursor chemicals needed for chemical weapons, and they are a nuclear power, possessing from 50-100 nuclear warheads with tons of backup plutonium. For over two decades, they have been involved in an arms race with the Pakistani program. Several Indian companies have been implicated in highly suspicious chemicals shipments and are involved in the construction of chemical plants in states that are developing chemical weapons. The United States has sanctioned some Indian companies for these activities.  Pakistan: Pakistan is a nuclear power with some 30-50 nuclear warheads, a large stockpile of HEU, and a major producer (like India) of plutonium.  It also has excellent delivery systems for chemical and biological agents as well as a wide range of other weapons.  Pakistan has an ongoing problem with Islamic extremism.  China: China is the world's third largest superpower with over 400 nuclear weapons (US=30,000; Russia=20,000; Britain=200; Israel=140; India=100).  China also possesses advanced delivery systems, including intercontinental ballistic missiles. A number of Chinese companies and individuals have been sanctioned by the U.S. government for their proliferation activities, and US-China relations have broke off because of nuclear espionage.  Taiwan: Since 1983, Taiwan has had an aggressive high-priority program to develop both offensive and defensive capabilities- the offensive capabilities of which scare China and are the stuff of numerous leaks and rumors.  U.S. intelligence officials are careful not to say exactly what Taiwan has or does not have.  Burma: This country's (Myanmar) WMD program started in the 1983-1992 period and focused on chemical weapons and artillery for delivering chemical agents. There have been many reports that Burma used chemical agents against insurgents.  Vietnam: Naval intelligence in 1988 indicated that Vietnam was in the process of developing, or already had, chemical weapons. Newspaper reports suggest that Vietnam may have obtained chemical weapons from the former Soviet Union.

Africa:  South Africa: This country is the premiere weapons state in the region, and they have an extensive WMD program. U.S. intelligence reports are almost totally classified. Public evidence abounds, however, that their programs are well-funded and have been underway since 1980. South Africa's weapons program operates with procurement of equipment and materials handled through a sophisticated network of front companies. Other South African officials have claimed all WMD capability has been destroyed or dismantled, but this claim has never been verified by outside inspectors. Newspaper reports citing U.S. intelligence sources suggest that former employees of South Africa's chemical weapons program may have helped Libya and other states develop chemical weapons.

A Note on the Environmental Impact