The category of “weapons of mass destruction” (WMD), like its expression in terms of proliferation, begs a question. Yet the chemical, biological, and nuclear weapons gathered under the acronym WMD are subject to separate regulatory processes, which take place within different timeframes. Since the 1990s, the word “proliferation” has also been associated with conventional weapons (anti-personnel mines, light weapons, etc.).

The term “weapons of mass destruction” (WMDs), which came into being at the end of the Second World War in connection with the appearance of nuclear weapons, designates weapons which are defined, in the first instance, in negative terms – as being non-traditional or non-conventional. As a category, its coherence is questionable in two respects. On the one hand, it is defined in many different ways – not all of which include the same types of weapons under WMDs: should radiological weapons be included alongside nuclear, chemical and biological weapons? High-explosive weapons? The malicious software used in cyberattacks? On the other hand, what qualifies as a weapon of “mass destruction” can be contested: chemical weapons, condemned as symbolic of the war’s horror at the end of the First World War, accounted for a marginal number of combatants killed in this conflict, while data around the number of fatalities caused by biological weapons are scarce. Rather than translating an empirical reality, the term WMD is implicated in the process of constructing an apparently exceptional threat, in the demonization of an enemy and attempts to legitimize contentious actions: in 2003, the United States justified their military intervention in Iraq with the (false) supposition that Saddam Hussein’s regime possessed WMDs; strikes by France, the US and the UK in Syria in April 2018 were undertaken in response to the use of chemical weapons by the Bashar al-Assad regime. The word proliferation, frequently paired with WMDs, underpins this process, designating both the dissemination of these weapons (nuclear weapons in particular) among an increasing number of actors, and an increase in the number of weapons these actors possess. Interpreting nuclear history in this light obscures the fact that most states have not sought to acquire nuclear weapons and that deproliferation processes (as in South Africa) also exist. More recently, the threat of WMD proliferation has also evolved to designate the fear that non-state actors, especially terrorists, might seize/use/possess these weapons. This fear was heightened by the discovery of the A. Q. Khan network in the early 2000s, leading to Security Councilresolution 1540.

Regulatory divergence

While WDM is a unifying term, the various processes around disarmamentnegotiations, prohibition and/or non-proliferation are clearly distinct, operating within different timeframes. Following the efforts of the Hague Convention of 1899 (declaration on asphyxiating gases), the Geneva Protocol of 1925 (which came into force in 1928) prohibited the use of asphyxiating gases and biological weapons in war. It dealt only with the use of these weapons and products (which are not listed) during armed conflict, and was supplemented at a later date by further texts that treated the two types of weapons separately. Negotiated in the era of bipolarity, the Convention on the prohibition of biological weapons (1972) was not accompanied by a verification mechanism although an Implementation Support Unit was established in 2006. The Organisation for the Prohibition of Chemical Weapons is charged with overseeing compliance with the convention of the same name, which came into force in 1997.

In contrast to these two documents, which imply processes of disarmament, the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) aims to limit the number of parties possessing nuclear weapons – the logic of disarmament, referenced ambiguously in Article VI of the treaty, does not appear as a priority.

Nuclear proliferation and disarmament, 2018

Source: compilation based on United Nations Office for Disarmament Affairs (UNODA),, Bulletin of the Atomic Scientists, 69 (5), September-October 2013.

Comment: The NPT came into force in 1970, creating a global geography that differentiated between states possessing a nuclear weapon (at the time, China, the United States, France, the United Kingdom, and the USSR) and those that had none. The treaty did not prevent other states from acquiring this weapon of mass destruction (North Korea, India, Israel, and Pakistan, all of them outside the NPT, as were Syria and South Sudan). In opposition to this proliferation, some states have signed treaties committing them to preserve vast nuclear-weapons-free zones (Latin America, Africa, Central Asia, South East Asia, Oceania, and Antarctica).

Non-Proliferation Treaty

The NPT, which was signed in 1968 and came into force in 1970, compliance being entrusted to the International Atomic Energy Agency (IAEA), identifies a club of legitimate nuclear powers. Highly controversial for this reason, it was nonetheless extended indefinitely in 1995, but has not been signed by India, Pakistan or Israel, and North Korea withdrew from it in 2003. In parallel, several nuclear-weapon-free zones (NWFZs) were agreed and arms control agreements were drawn up between the major powers (Strategic Arms Limitation Talks [SALT], Strategic Arms Reduction Treaty [START]). From 2007 onward, as the campaign to abolish nuclear weapons got under way (ICAN), the aim of a achieving a world without these weapons gathered momentum (Global Zero, Security Council resolution 1887, New START agreements); a Treaty on the Prohibition of Nuclear Weapons was agreed in 2017 but has not been signed by the existing nuclear powers.

Treaty on the Prohibition of Nuclear Weapons, 2018

Source: United Nations,

Comment: This map shows the geography of the UN General Assembly vote in July 2017. The states that were against a nuclear weapons ban did not take part in the vote. They consisted of those which already had nuclear weapons and their allies; the Netherlands was the only country to take part in the vote and to vote against. The majority of member states were for: these were mainly from the South (from Latin America, Africa, the Middle East, and South East Asia) but also from Europe (Sweden, Ireland, Switzerland, and Austria). Ratification of this treaty has been open for a short time and remains limited (19 states in January 2019). ICAN, the NGO that militated in favor of the treaty, obtained the Nobel Peace Prize in 2017.

During the 1990s the term “proliferation” was increasingly linked with conventional weapons (anti-personnel mines, small arms and light weapons) both in the media and in the discourse of relevant actors – underscoring the fact that the weapons causing the highest number of fatalities, especially in civil wars, are not WMDs.

Proliferation of light weapons, 1962-2016

Source: Norwegian Initiative on Small Arms Transfers (NISAT), Database of Small Arms Transfers, 1962-2016,

Comment: These curves complete the map showing the trade in light weapons by contributing a chronology for the top ten exporting and importing countries between 1962 and 2016. Although the figures are in common currency, which exaggerates recent figures on account of inflation, the international trade in light weapons substantially increased from the late 1980s onwards. The United States imports the bulk of international trade, more than 2.5 billion dollars worth in 2016, whereas exports are more divided between the United States, then Italy, Germany, and South Korea.

In consequence, and partly through initiatives by coalitions of civil society actors (International Campaign to Ban Landmines, Control Arms campaign), we have seen a series of initiatives and regulatory endeavors: the Ottawa Treaty in 1997, Security Council resolution 1467, the Arms Trade Treaty in 2013. Yet many obstacles remain: traceability issues (trafficking), unwillingness on the part of user states, the widespread availability of weapons in conflict zones and areas of lawlessness.

Small arms trade, 2012-2016

Sources: Norwegian Initiative on Small Arms Transfers (NISAT), Database of Small Arms Transfers, 1962-2016,; Small Arms Survey, Trade Update 2017,

Comment: The data relating to international trade in light weapons (pistols, rifles, and machine guns) are mainly produced by think tanks – in this case, the NISAT Initiative and Small Arms Survey –, especially as it involves assessing the transparency demonstrated by exporting countries. The United States is by far the largest importer of small arms while the main exporters are the United States, followed by Italy and Germany and then South Korea. Only the European states show transparency in their exports. At the opposite extreme, the Gulf countries but also Israel and North Korea prove to be very opaque about the destinations of their exports.

Arms Trade Treaty, 2018

Source: United Nations,

Comment: The map shows the geography of the 2013 UN General Assembly vote on a treaty designed to regulate the arms trade (but not in nuclear, bacteriological, and chemical weapons). The large majority of states in Europe, America, Africa and Oceania voted in favor while three states voted against: Syria, which was at war, Iran, and North Korea – all states that are very opaque about their arms exports (particularly light weapons). Other countries with an important arms trade manifested their disagreement by abstaining from the vote: these were Russia, China, India, Saudi Arabia, and Egypt.


To quote this article

" Proliferation " World Atlas of Global Issues, 2018, [online], accessed on Mar 15 2021, URL:


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