To be sure, many parties have already crossed the line.  There have been military factions within sovereign states who took it upon themselves to release WMD, or use clandestine, non-state groups to do their dirty work.  It is the proliferation of such weapons into the hands of these non-state, sub-national actors that draws the concern of most experts (Hoffman 1997).  The mindset of many terrorists is that they are drawn to explosions like pyromaniacs are drawn to fire.   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/or concordance with nature.  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 novels which usually involve a convention or sports venue).  It is surprising that there are not more instances of terrorist use of poisoning since many toxic elements are easily available in relatively large quantities (e.g., arsenic, antimony, lead, mercury, and thallium) and the heartlessness it takes to use such substances is not beyond the average murderer (Emsley 2005).

A BRIEF HISTORY OF WMD       

    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, which burns and destroys lung tissue (e.g, pulmonary edema) and is found practically everywhere, often in large quantities.  On the battlefield, chlorine gas appears as a big cloud hugging the terrain and taking hours to dissipate (see The Chlorine Institute for more information).  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 everyone from a large-scale chemical attack, and people are chemo-phobic anyway, so even those only at the smell threshold will overload emergency rooms.

    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 Senators 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 Nunn-Lugar legislation is designed to help enhance Russian security.  Often the most encountered phrase is "loose nukes" but weapons-grade plutonium smuggling is another concern.  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, and few countries contribute to post Cold War nuclear security cleanups. CBR warfare does requires intensive intelligence work on development, deployment, and delivery capabilities, but there is the less-technical problem and concern regarding "DIRTY BOMBS," formally called radiological dispersion devices, which use conventional explosives to fling radioactive isotopes in a plume of dust which can contaminate at least a 60-square block area.  Most analysts believe that no more than 10 people would die from radiation poisoning after a dirty bomb attack.  The immediate blast area is where the most radiation exposure occurs.  The aftermath death toll depends on topography.  Dirty bomb attacks are often called I-cubed attacks (for ingestion, inhalation, and immersion).  It's hard to kill a lot of people with an ingestion attack because the most typical vector would be a water reservoir which dilutes the material.  An inhalation attack, often called a smoky bomb, might burn, vaporize, or aerosolize something like polonium-210 in a confined space or area, and besides some immediate deaths there would be some lingering cases of lung cancer.  An immersion attack involves throwing or spraying somebody with drops of contaminated liquid, and besides some immediate radiation burns, this kind of attack assumes the victim will wipe their face with their hands, eventually transporting the substance to the mouth.            

    Dirty bomb acquisition has been a declared intent of the al Qaeda terrorist group which 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 many lower-grade nuclear materials required for a dirty bomb.  Cesium-137 in the form of powdered cesium chloride is the most likely substance for a dirty bomb, and it is commonly found in hospitals and industrial facilities.  Other radioactive isotopes can also be easily found, but Cesium-137 is especially nasty.  It penetrates lead shielding and even in its non-radioactive form is highly poisonous.  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.  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).

    Outside of Russia, there are additional places where nuclear security isn't up to standard.  Most countries consider US Energy Department security criteria too demanding.  India, for example, hasn't been completely cooperative, and China has secured only one civilian reactor.  In all, there are 43 countries with more than 100 research reactors or related facilities that store enough highly enriched uranium nuclear materials to make several bombs, and only about 20% of these sites are properly secured.  Rather than try to go after fairly better-protected Russian material, a superterrorist is far more likely to go to India, China, Switzerland, or Italy (or somewhere else with relatively looser security) and knock off the night watchman, lower the chain-link fence, and drive off with sufficient materials for a nuclear device.  After that comes the easy part of assembling the nuclear weapon -- the recipe is on the Internet and keeps showing up despite best efforts to "police" this kind of thing, and then, terrorist groups like al-Qaeda are known to have CD-ROMs burned with downloads of related Internet pages. 

Planning & Strategy
    The U.S. government has always had response plans in place for superterrorism, and the basic foundational or theoretical basis for such plans is to effectively make the shift or transition from crisis management (predominantly a law enforcement response) to consequence management (restoration of services in which the federal government helps out).  In addition, there are continuity of operations plans (where the government helps itself out).  In general, what planning has been done is beset by problems of fragmentation.  For example, click here (and then mouse magnify) for a glimpse of the organization chart which existed prior to 9/11 and involved 27 different agencies.

    National Security Presidential Directive 17 decrees that after any terrorist WMD attack, including biologicals and chemicals, the U.S. will engage in a retaliatory response.  Preparedness for such response is rehearsed via the scenario/drill/exercises known as TOPOFF (Top Officials), "no notice" drills that usually last 5-7 days, and involve fictional attacks by fictional terrorist organizations.  Billions of dollars have also been invested in hospital systems, increasing the number of smallpox vaccines, making available potassium iodide tablets for radiation poisoning, and providing more stock for the nation's National Pharmaceutical Stockpile - secret stashes of medicine at locations throughout the United States.  The development of vaccines for each and every contingency is a policy priority.

   In terms of strategy, it is important to note that never does the U.S. commit to the definite use of nuclear retaliation, and the way it is put is that the U.S. never rules out the possibility. This indefiniteness is not so much there for democratic reasons as it is part and parcel of a long-standing evolution of deterrence doctrine into the modern notion of reassurance. To understand this evolution in strategy, one needs to understand the long-standing practice of nuclear deterrence, which was the basis of the Cold War.  One also needs to understand that in some quarters it is mistakenly thought the only sure way of disintegrating a stockpile of chemical and biological weapons about to be used is to nuke them.  Nuclear attacks on CBRN targets generally result in immediate destruction but also raise the possibility of increased harm through debris fallout.  

    The basic idea of deterrence is to prevent attack by threatening overwhelming retaliation. The military definition of this term involves a combination of magnitude and probability, which requires having a large stockpile of weapons and the willingness to use them in a system of layered precautions.  This game of deterrence works best between two enemies who are about evenly matched and equally clever.  For example, both the U.S. and Russia 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 most of the cities in both countries many times over.  On a practical level, all you would need for a nation the size of the U.S. is about 700 nuclear weapons -- as that would destroy about 50% of the population and 65% of the economic infrastructure.  Overkill is unnecessary.  Destruction in the 50% to 60% range will do.  These practical levels are known as plausible deterrent requirements.    

    The START treaties are to be thanked for curtailing the use of multiple warheads, a prime contributor to overkill. When the Soviet Union broke up, the remaining 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 are not being regularly maintained. We are currently in a START III phase which is aimed at curtailing nuclear submarine forces (although China has upped the submarine arms race in recent years).  Some key principles of this era we now live in include the ideas that: deterrence is not the same as prevention; and dismantling is not the same as elimination.  Further, inspections don't work.   

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.  For some terrorists, chemical weapons are better than biological ones because they're easier to calibrate and far less likely to spread out and harm fellow personnel.  With the exception of HAZMAT preparation, countering a chemical weapon attack is usually carried out in much the same way as countering a traditional attack.

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 laboratories. For example, a 1979 "meat packing" accident in Russia released an anthrax epidemic that killed over 1000 people. "Near misses" have also occurred in American facilities. Some experts have argued the appropriate response to a biological attack is nuclear (a kind of spite from the grave strategy), but there is much research into finding more defensive ways to survive.  Extensive planning and preparation is required, as the government's new planning tools at Pandemicflu.gov illustrate.  Biological warfare is too easy to start and too hard to finish. Terrorists who engage in it should normally expect severe retaliation of some kind.

    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. The 1918 strain is also known as the Spanish flu, and it is a subtype of the Avian (H5N1) flu, which constitutes a current pandemic threat.  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.  Experts such as Michael Fumento suggest too much fuss is made over pandemic threats today because new antivirals, like Tamiflu and Relenza, are tremendously effective against H5N1 and its mutants, and if regulatory approval could be expedited, it would be easy for many countries to stockpile enough for each and every citizen.  Antivirals, however, are subject to the same degradation as antibiotics, and expert opinion varies on estimates of pandemic mortality.  The World Health Organization (WHO) says in the worst case, 100 million would die, but the usually-cited estimate for deaths in the United States is 500,000 (the same number which died in 1918).  The American government's stockpile supply, assuming it is not depleted by efforts to contain an outbreak somewhere else in the world, will only cover about 25% of Americans.  Mark Helprin, among others, have suggested that more investment needs to be made in America's biodefense infrastructure, such as: create a dozen centers for research immunity, modularize field hospitals, double the output of nursing and medical schools, promote the self-sufficiency required for long quarantine, unleash and encourage the great drug combines, and quicken reaction to outbreaks here and abroad.       

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 only found naturally 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 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 is so pure that 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 about 20 pounds of plutonium or 60 pounds of enriched uranium (about the size of a football), but technically, a nuclear weapon could be built with less than 18 pounds of plutonium or 55 pounds of highly enriched uranium.  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.

    Nuclear smuggling is of great concern.  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.  Below are some maps of two states to be especially worried about -- Iran, because they likely intend to use nuclear weapons aggressively; and Pakistan, because terrorists have been trying hard to break into the nuclear sites.

    Besides nuclear weapons, there are nuclear power plants to worry about.  In America, 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.  Also, since the oceans were used many years for dumping weapons, some environmentalists consider these scattered sites to be potentially dangerous.  A number of scientists and some respected international organizations believe it is best to leave the underwater sites alone, especially if they are in deep water.  Other experts disagree with that conclusion.  During the past four decades there have been several incidents involving leakage of sea dumped weapons. For example, some material has shown up on beaches and fishing nets. There is too many uncertainty to draw any firm conclusions.    

SUMMARY AND CONCLUSIONS

    Few states admit they possess weapons of mass destruction.  The United States has taken the lead in destroying many of its weapons, but still maintains a stockpile of about 30,000 tons of chemicals. Russia has declared 40,000 tons. India admits to only having them 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."  Third World nations feel free to stockpile chemical weapons "without fear of repercussions from the international community."  Parts of the world are engaged in destabilizing arms races.  Middle Eastern countries, in particular, have always expressed an interest in pursuing WMD.  In Asia, nobody knows the interests and/or capabilities of some countries.  Europe tends to be the place where the most skill and sophistication exist in terms of weaponization expertise.  Clearly, global cooperation is needed to advance the cause of nonproliferation (see Lecture on International Arms Restraint).