Chemistry is a branch of science which can all too readily be discounted as potentially fruitful for military applications. While we will consider Chemical Weapons in the narrow sense in this chapter, they represent only one application of chemicals to war. The great achievement of the early chemists was the production of gunpowder, and it is in the field of explosives that they may yet have much to offer. As with all aspects of modern military technology, the new weapons draw on many disciplines. Chemical reactions can provide power in the form of an explosive release of energy, or as a controlled propulsive force. Chemicals can kill through direct effects on different vital functions of human beings, and they can also provide the protection against such weapons. They can provide healing drugs to assist casualties' injuries to heal rapidly, or disabling drugs to affect the will of a soldier to fight. Chemicals can be used to attack indirectly through the food chain, or can provide extra resources through fertilisers and pest control. In sum, chemistry is used offensively and defensively, and as with so much of modern science, the products of civilian research play an important role in the security of a nation.

In modern strategic jargon, Chemical Warfare refers only to the use of chemical substances which kill or disable living organisms. While chemical weapons may be dropped on buildings, equipment or dispersed over territory, it is done to deny access by vulnerable human beings. Agents are characterised by five qualities: Stability, Potency, Persistence, Delay Time and Cost of Production (1). Stability is a measure of how well a particular chemical agent retains its potency. Technical developments have worked towards producing stable agents which can be more easily stored and handled, while at the same time remaining effective for many years. The production of binary nerve agents in the United States greatly enhanced the stability factor of their chemical agents. Potency reflects the amount of agent necessary to produce the desired effect. Development work directed towards increasing potency allows either a wider area to be covered, or greater range with reduced warhead payload. Some agents disperse and lose their effectiveness in a relatively short- time (often depending on wind); whereas others can remain effective for days. The tactical situation will determine whether a persistent or non-persistent agent is preferable. The delay time is a measure of the time taken between contact with an agent and the onset of the required effect. It will normally be advantageous to minimise the delay time. Finally the cost of production of any chemical agents is important, as large quantities are required for effective operations, and technology can be directed towards minimising unit costs.

The range of chemical weapons, which have been developed in the 20th Century, attack the human vital systems in different ways. Blister agents, causing burns and skin blisters, date from mustard gas in World War I. Lethal concentrations are difficult to achieve, and protection is relatively easy. Blood gases, like Hydrogen Cyanide, interfere with cell respiration. Protection can be achieved through the use of gas masks, but it is possible rapidly to saturate the breathing filter with such agents. Lung irritants, such as Phosgene, attack the respiratory system, and again gas masks provide protection. Nerve agents affect the body's ability to control muscle action, and lead to death through respiratory failure. Some such as Sarin must be inhaled, while the V agents can be absorbed through the skin. They are rapid in effect and can be either non-persistent or much longer lasting low volatile substances. Protection can only be achieved by whole body and gas mask coverage.

There are occasions when chemicals which incapacitate rather than kill may be useful. This is the case with riot control agents, and also in certain counter- terrorist operations. To incapacitate an individual, it is possible to attack either the body or the mind with chemicals. The widely used phosgene-oxime (CX gas) causes severe nose and eye irritation to incapacitate. The drug LSD has been suggested as psycho-chemical agent which would incapacitate by producing hallucinations. However as predictability of effect is an important aspect of the use of incapacitating agents, mind altering drugs have few attractions at present.

In addition to agents lethal and incapacitating to mankind, it is also possible to target other living organisms. Between 1965 and 1971, the US sprayed the South Vietnam jungle with some 10.6 million gallons of defoliant chemical known as Agent Orange. While this was done to expose the enemy, the use of such chemicals on both vegetation and livestock to deny food resources is also possible.

Looking to a possible future where hostile parties might use the full spectrum of chemical agents, a number of avenues for productive research are apparent. On the offensive side rapid acting agents, with precise and predictable consequences, which can be produced easily and safely will be sought. As international control of chemical weapons is tightened, methods for more covert production may be sought by some states. The chemical characteristics must take into account the available countermeasures. Properly fitted gas masks reduce toxic concentrations in inhaled air by a factor in excess of 100,000 (2). The filter in the mask uses activated charcoal to absorb vapour, and paper to filter particles. Reagents against specific small molecule chemicals, like Hydrogen Cyanide, can also be included. Skin protection can be provided by impermeable material such as rubber, or liquid repellent air-permeable charcoal-lined cloth. The cloth protection is much less tiring to work and rest in. Collective protection for troops can be provided in filtered accommodation. The other necessary part of any defensive system is a reliable detector for the presence of chemical agents. The detector must give sufficient warning for protective measures to be adopted. Finally, in the event of the chemical being absorbed into the body, it may be possible to provide an antidote. The continuing debate over the Gulf War Syndrome (3) indicates that taking precautionary drug protection against chemical and biological threats may have longer term drawbacks. Chemical decontamination is also a requirement if operations are to be continued after an attack by a persistent agent.

Research can offer improvements in the effectiveness of chemical weapons, the efficiency of protective measures, the success of antidotes and the ease of decontamination. The widespread horror of chemical warfare and the Chemical Warfare Convention (CWC) makes such research limited in democratic states.

Yet the number of nations which may resort to chemical warfare is increasing. The US Office of Technology Assessment that Egypt, Iran, Iraq, Israel, North Korea, Libya, Mynamar, Syria, Taiwan and Vietnam have either a chemical warfare capability or considerable interest in the development of such a capability.(4) As one study into the problem (5) has highlighted, pesticides, which are closely related to nerve agents, are widely used and increasingly produced in developing countries. The pesticide production facilities could be used to produce nerve agents, especially as the development of binary weapons has made manufacture much safer. Even without such an ability, some of the pesticides can act as chemical warfare agents in sufficiently high concentrations. The CWC bans activities involving particular chemicals, but does not ban the chemicals themselves. Verification of adherence to the terms of the Convention will therefore be difficult, and require continuing research into ways in which states might evade compliance.

Comprehensive chemical disarmament is the ideal, and the CWC has been a significant step forward in the process. Nevertheless, there is little prospect of the elimination of the dangers of chemical attack. The Iran/Iraq war has already shown the impact of chemical warfare, with the attack on a civilian town by Iraq in 1988. Although no chemical weapons appear to have been used in the Gulf War, all the coalition forces were constrained by the threat of such an attack. Since then, Japan has undergone two terrorist attacks using Sarin. There is therefore ample evidence for a continuing need for research into chemical warfare in order to provide effective counters.

At the lower end of the spectrum, a riot control agent which disperses a mob without any risk of injury is needed. It may be that research into psycho-chemicals could be productive. It is possible to envisage an agent which could generate short-term amnesia, perhaps an appropriate phobia to cause dispersal of a crowd, or remove all aggression. These are likely to be safer approaches than the agents which produce physical discomfort. Inevitably the difficulties of predicting concentrations of gas in riot areas, make injuries possible through the overstimulation of body reactions, when using those chemicals which produce physical reactions. Work on non-lethal incapaciting agents will require significant continuing research.

In the field of lethal chemical agents, we need to consider how potential users of chemical weapons will develop their capabilities. The current range of weapons provide a full spectrum of effectiveness if they are able to penetrate to the targets. Undoubtedly advances can be made in each of the qualities discussed above, but the most productive area for research will be in increasing the penetration of the agents. This has implications for delivery systems and dispersal mechanisms as well as the chemical composition of the agents. Agents with elements which rapidly saturate filtration systems, or are able to pass through unattenuated, could prove more effective. Perhaps agents which specifically attack the protective materials are possible. Another avenue of approach would be to attempt to deceive detection systems, so that troops had insufficient warning.

For the defender, research will be needed for the development of improved protection systems. Whatever the efficacy of the Chemical Weapons Convention, it would be wise for nations to retain the technology to protect themselves against this threat. The material for protective clothing must not hamper operations, but must protect against all threats. The filters for gas masks must be both effective and long lasting. It may be that the development of personal oxygen generating equipment would offer complete security against inhalation threats. The research in this area must also extend to vehicle and building protection, and will inevitably cover the associated threats from both nuclear and biological weapons.(6)

In the field of counter-measures following chemical contamination, there remains much work to be done. The decontamination of equipment and surfaces of persistent agents is a laborious process. Effective, rapid and cheap decontamination reagents are needed. The antidotes for individuals suffering from chemical exposure are even less satisfactory. For rapid acting agents, there is little time to administer antidotes, which in any event have side effects which incapacitate. The ideal medical countermeasure would be a preventive drug, which would be taken before the chemical attack, and would have no side effects. If developed this panacea drug could alter the balance of advantage in chemical warfare.

Moving away from the narrow definition of Chemical Warfare to the wider, it is clear that the Chemist is a key developer of conventional killing systems. High explosive in munitions and propulsive power from bullets to missiles are all the products of chemical reactions. Improvements in conventional munitions have come from the work of the Engineer in designing explosive charges to match specific targets. Nevertheless, the characteristics of the explosives remain a key feature. For a long time weapons have divided into two classes: the target penetrator and the area weapon. In the last century, this would be the difference between the assassin's bullet and the anarchist's bomb. The requirements for each type of weapon system are quite different. For the bullet, shell or missile, accuracy and predictability of propellant are essential. The explosive content can be small, if it is designed to exploit the target's vulnerability. For the area weapon such as the high explosive bomb, the explosive power for a given weight becomes the important factor. Much work has been done on the development of fuel-air explosives, which can give a large and uniform overpressure over a wide area. The development of explosives with considerable area destructive capability offer attractions to the military commander as an alternative to tactical nuclear weapons.

Development work on chemical propulsive fuels also has far to go. Missile motors have moved away from the liquid fuel versions, which made them so vulnerable in their slow reaction times. Yet solid-fuel motors require much greater technological expertise if they are to be reliable and predictable. The fuel must not only burn in the expected manner, but must also have a long life without deterioration in performance. At the same time, the more power that can be generated for a given weight of fuel, then the greater the warhead that can be delivered over a given distance. All these aspects of propellant design are areas rich for the work of the chemist.

In one other area of propulsion, the efficiency of fuel is of critical importance. Military forces depend on fuel oil for nearly all their ships, vehicles and aircraft. While the dire predictions of a world without oil have temporarily been quieted, oil is a finite natural resource. In any event, the sheer mass of fuel used in war brings with it enormous logistic burdens. Research into fuel technology offers considerable benefits. It may be that an increase in cost of fuel is acceptable if it reduces the capital cost of a particular weapon system. One could envisage an aircraft which required a specific range/payload combination being produced with a simpler design using a more efficient fuel. If fuel could be generated compactly where the army was fighting, its logistic supply problem would be reduced. Rechargeable electric cells offer a clue, but remain ludicrously inefficient in power to weight ratios when compared to the internal combustion engine. The development of fuels which allow prolonged operations requires a parallel development of lubricants which can keep mechanical parts operating without attention for longer periods. In both these fields, it is likely that commercial pressures will ensure that research continues which may have military application.

The final area for military interest in the work of the chemist is in pharmacology. The advent of penicillin was as important in warfare as many new weapons. If the aim of a particular weapon is to kill, its effectiveness can be reduced if the rate of survival is increased through medicine. The use of antidotes in chemical warfare has already been discussed. Immunisation against biological agents will be considered in Chapter 11. The importance of drugs to promote rapid return of casualties to combat fitness is obvious. Of increasing importance will be drugs to derive maximum effort from troops when required. The advent of 24 hour operations has made the resting of troops even more difficult than in the past. The use of drugs to utilise fully rest periods, and to stimulate maximum performance when needed may become the norm. When this extends to drugs which reduce fear, or affect the soldier's mind in some other way, a number of difficult moral questions arise. Nevertheless, the possibility of drug- enhanced combat performance is one which cannot be discounted in future conflicts.

The chemist has therefore much to offer the military in new technologies. In chemical warfare the research must be virtually exclusively military. Even where the use of such weapons is prohibited, there will be a continuing need for research into protective measures and into CWC verification techniques. In fuels and propellant technology, commercial considerations are likely to make civil research the most productive path. In healing drugs and techniques, civil medical research will produce applicable techniques. For drugs tailored to enhance performance under the stress of combat, it is likely that a specific military research programme would be necessary.

Notes to Chapter 9

1. 'Chemical Warfare: A Primer on Agents, Munitions and Defensive Measures' by E.M.Kallis, Congressional Research Service Report 81-97F of 27 April 1981.

2. 'Chemical Warfare and Chemical Disarmament' by M.Meselson & J.P.Robinson in Scientific American April 1980 pp 34-43.

3. There have been widespread reports of post-War illnesses among US and UK troops who took part in the Gulf War. While there does not appear to be any conclusive evidence of a single cause, a number of experts believe that the mixture of precautionary drugs administered to troops, liable to come under biological or chemical attack, may have been a significant factor.

4. Quoted in "The Devil's Brews", Bailrigg Memorandum 16 edited by R.Ranger Lancaster University 1996 p 45.

5. 'Chemical Weapons and the Third World' by G.K.Vachon, Survival, March/April 1984 p80.

6. 'Chemical Weapons and Western Security Policy' by the Aspen Strategy Group (University Press of America 1988) p10, reported that: 'It seems improbable that technological changes per se could put defense at a disadvantage in any decisive way, provided that Western intelligence is adequate to give warning of new and threatening developments.' This is an overly optimistic assessment in the author's view. A more sobering review of defensive technological capabilities appears in: Deterring Chemical Warfare: US Policy Options for the 1990s by H.Stringer (Pergamon, Oxford 1986) pp 48-9.