The term Weapons of Mass Destruction is applied to Nuclear Chemical and Biological weapons. In fact these three categories differ very significantly in their political, military and technical aspects. There is some overlap between Biological and Chemical weapons, eg in the area of recently developed body regulators or toxins but in general it is not helpful to consider the three sorts of weapon together.

  Nuclear weapons have been developed and tested by a number of countries but used in war only against Japan in 1945. There is no doubt about the technical ability of the five states recognised as Nuclear Weapons States under the NPT to produce effective weapons of this class. Nor is there serious doubt about their military effectiveness.

  Three other states are nuclear weapons possessors, India, Pakistan and Israel. The first two are certainly capable of producing nuclear explosions. How effective they would be in delivering reliable nuclear weapons is more doubtful, though they could probably deliver a few. Israel has many more weapons, perhaps more than 200 and could almost certainly deliver them effectively (though its production facility is now old and dangerous).

  Nuclear weapons are relatively small; they can be introduced into artillery shells of 6 inch calibre or more. They need, unless fissile materials are obtained from an external source, a substantial physical infrastructure. Advanced design needs a major input of scientific and technical skills. A crude device is relatively easy to produce, given fissile materials; a really advanced one very difficult.

  Chemical weapons span a range from simple industrial chemicals such as chlorine or phosgene (both used in the First World War), through nerve gas, invented in the 1930s and closely akin to pesticides, to highly sophisticated chemicals, such as the Soviet Union was working on, able to penetrate most defences. Generally, chemical agents require quantities of tons to be effective on a mass scale (as opposed to assassination or terrorist attempts). That has implications for delivery and manufacture. Production requires industrial scale plant, and movement of many tons of materials. For the simpler kind of CW, any state with a reasonable chemical industry can speedily become a possessor. That in turn means that unless countries are to be denied economic and industrial development the potential for CW proliferation will always be there.

  CW is proven in use at the tactical level. There is much more uncertainty about its utility at a strategic level, though its psychological impact could undoubtedly be great. For delivery, cruise missiles, aircraft, or in tactical use (as in WWI), artillery are appropriate methods. Ballistic missiles are unsuitable for mass destruction use, except with advanced fusing and sub-munitions.

  Biological weapons require much less bulk than CW. Grammes can cause widespread fatality, if they can be disseminated. The science is more advanced than for basic CW, but not much. Bacteria and viruses can be cultured relatively simply and even the knowledge for genetic modification to make them more resistant to countermeasures is becoming more widespread. They thus share many of the characteristics of CW, but are in general more lethal weight for weight, and need production facilities on a much smaller scale.

  Military utility is largely unproven but because of the small scale of production facilities and the lethality of small amounts BW is technically tempting for criminal or terrorist use. The targets could then be economic or commercial. Delivery for panic inducing or extortion purposes poses many fewer technical difficulties than for mass destruction use.

  Politically and legally nuclear weapons are recognised. They have an accepted role, for the present, in the strategies of the NWS and of NATO. The NPT recognises their legitimacy in the hands of the NWS. There is an obligation to move to their total abolition but despite various pressures their current existence is not under serious challenge. The position is very different for CW and BW.

  There are Conventions essentially outlawing possession let alone use. Very few states argue for their legitimacy, though there is a particular problem in the Middle East (on which see below.) It should be an important political objective to prevent their acquiring either legitimacy or a fundamental role in any state's strategy.

  Because of the very different natures of Nuclear, Chemical, and Biological weapons different regimes are appropriate and necessary to prevent proliferation. The facilities for the production of fissile material are fairly readily identifiable, and so are major chemical complexes. BW facilities are much more easily concealed and require much more intrusive inspection to counter. For none of the kinds of weapons can either supplier regimes or inspection prove entirely effective. The objective must be to create such a web of obstacles that the difficulties and costs of proliferation become such as to make the game not worth the candle. At the same time, the objective must be to remove the political drivers of proliferation.

  Most would be proliferators are driven by regional security concerns. Israel has weapons of mass destruction because it fears attacks from the region. The same argument applies to Iran's efforts to acquire such weapons: with the threat from Iraq there is a real security need, aggravated to the extent that Iran is denied conventional weapons. In addition, Iran is concerned about the India/Pakistan confrontation. (Pakistan itself is motivated by Indian possession.) Most other players in the Middle East are also driven by regional concerns, and possession by one player can frustrate the application of arms control limitations in others. Thus Egypt will not sign the CW convention until Israel joins the NPT. India and Iraq are exceptions to the general thesis, and some in the region see Iran and Israel in the same light.

  India seeks nuclear weapons because it feels that they are a passport to the top table. Iraq for reasons of regional hegemony or aggression. Both of those drivers are very difficult to deal with. North Korea is another severe problem but more capable of political solution in the foreseeable future.

  As regards the effectiveness of no-proliferation regimes, the NPT has been a success. It is generally accepted in the letter and the deed. India and Pakistan refuse to adhere, as does Israel. The last may join if there is a political settlement in the Middle East. Pakistan would join if India did. Only India seems likely to be obdurate about joining. A small number of states party try to breach their obligations, notably Iraq before the Gulf War. Iran may try to do so for regional reasons. For most of the World there is now a much reduced salience of nuclear weapons, even for Russia, despite its need to rely more on them to deter aggression than in the past because of its conventional weakness. Reasonable progress has been made toward the ultimate objective of Article VI with the recent reductions in US French, British and even Russian systems.

  The Comprehensive Test Ban Treaty has been rejected by the US Senate. There are other nuclear capable states whose ratification would be necessary to make it effective. At present it is important as a political symbol and aspiration rather than as a concrete non-proliferation measure. The same is true in even greater measure for the proposed fissile material cut off treaty. Even if ratified and implemented its significance would be symbolic rather than practical. There are very significant quantities of fissile materials in existence. Getting them under proper control, particularly those in Russia, is a more urgent need than the proposed treaty.

  The ABM Treaty is a vital part of strategic stability. It has worked very well in that context. Significant change in pursuit of the chimera of invulnerability would greatly to be deplored. Both Russia and China would find a US National Missile Defence destabilising. There are also severe doubts as to whether it would be technically feasible in practice. Certainly no such system would deal with WMD of whatever sort delivered by package or courier.

  The CW Convention is a reasonably effective regime. The inspection provisions are not so effective as they could have been but are at least a start. There is major significance in the development of a norm against these weapons.

  The last point is true also of the BWC for which there is no verification machinery. Because of the scale of manufacture such machinery will be very difficult to make effective. To be effective it would have to be highly intrusive, beyond what many states will tolerate. Even with deeply intrusive inspection there could be no certainty of detection of violation but it would add to the web of difficulty spread before proliferators.

  That point applies to the export control regimes. As technologies become more widespread the difficulties of control, especially when as in Russia and China central authorities may only have imperfect knowledge of what is going on, and where there are major financial incentives, become greater. The regimes have been very useful but need to be suppplemented by good intelligence activity.

  The UK can have a modestly effective role in encouraging the signature and ratification of treaties. Given the excellence of its intelligence activities it can be well placed to press for the remedying of breaches. At the end of the day, what is required is political effort to reduce the incentives for proliferation, and to put pressure on proliferators. Signature of treaties has been useful in creating norms but they have, by and large been established. The major exceptions are the Indian sub continent and the Middle East. The latter requires a just settlement, and constructive engagement. The former depends upon India's coming to a more balanced view of what gives position in the World.