Weapons of mass destruction (WMD) are a serious international concern and have been at least for nearly a century. After World War I, the Geneva Protocol of 1925 prohibited the use of chemical and biological warfare. The advent of nuclear weapons, with their extraordinary destructive capacity, made the proliferation of WMD an even greater concern after the Second World War.
Moreover, during the post-Cold War period the dangers of proliferation of WMD have increased due to regional tensions, the dissolution of the Soviet Union (and resulting looser controls over weapons scientists and dangerous materials), and the ready availability of sensitive technologies. More than ten States have active WMD-related programmes, and probably about ten more have capabilities to start them.
At the same time, non-State actors (transnational organized criminal communities and international terrorist networks) today are seen as playing an increasingly active role in unauthorized access to and proliferation of sensitive materials, technologies, and weapons. After 9/11, the risk of such actors using WMD components as a tool for blackmailing governments has become a real scenario, still with low probability but with highly significant - and disastrous consequences.
The international community has responded to problems and challenges in two major ways. The first has been the elaboration of multilateral international treaty regimes intended to prevent the proliferation of WMD. These include the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), the Chemical Weapons Convention (CWC), and the Biological and Toxin Weapons Convention (BWC). The second approach has been the formation of non-treaty arrangements, generally known as "suppliers' clubs", aimed at preventing the proliferation of technologies and equipment that could be used by a "proliferant" State or non-State actor to develop WMD and/or delivery systems (e.g., ballistic or cruise missiles) associated with such weapons. These organisations are: the Australia Group (chemical and biological technology); the Zangger Committee and the Nuclear Suppliers Group (nuclear); and the Missile Technology Control Regime (MTCR).
A particularly important role in detecting non-compliance to nuclear non-proliferation is played by the International Atomic Energy Agency (IAEA). Its inspection mechanism has proved to be efficient and balanced even in such complex situations as Iraq.
For various reasons, these treaty and non-treaty regimes have been under severe stress in recent years. The situation demands a new international agenda of action against the proliferation of WMD. For example, within the NPT regime, nuclear-weapon States and non-nuclear weapon States frequently disagree over Treaty commitments to negotiations regarding nuclear disarmament and to provisions to prevent the diversion of nuclear materials to nuclear weapons purposes. The Indian and Pakistani nuclear weapon tests of 1998, the de facto nuclear weapon status of Israel, and the North Korean nuclear weapons programme also pose significant challenges to the NPT.
Meanwhile, States parties to the BWC have not achieved consensus on a legally binding protocol to provide the convention with a "verification" mechanism. Despite conclusion of the CWC - which mandates the elimination of an entire class of WMD and establishes an international organisation and detailed verification regime to ensure compliance - many countries are suspected of possessing chemical weapons programmes. Issues of compliance are essential, and the failure to address non-compliance in a satisfactory manner is perceived as undermining the viability of the nonproliferation regime.
The growing perception that these mechanisms have been inadequate to constrain the proliferation of WMD technology and the development of increasingly longer-range missiles has led to alternative approaches. On the one hand, there has been a cooperative international approach to assist countries in the former Soviet Union that have technical and/or financial difficulties living up to their non-proliferation commitments. On the other hand, the US has also begun to place greater emphasis on deterrence and defence against these threats, as evidenced by robust programmes for counter- proliferation, such as the 2003 Proliferation Security Initiative.