Are Nuclear Weapons Illegal?

The International Law Obligation to Pursue and Achieve Disarmament

John Burroughs – director of the UN office of the International Association of Lawyers Against Nuclear Arms – explains why it is illegal to use nuclear weapons and why the modernization of nuclear forces conflicts with the universal obligation to disarm.


ICAN: Does the use of nuclear weapons violate international law?

John Burroughs (JB): The threat or use of nuclear weapons violates fundamental rules of international humanitarian law, the law of armed conflict and the UN Charter. It is prohibited to inflict indiscriminate and disproportionate harm on civilians and civilian objects, to cause widespread, long-term and severe damage to the environment, and to cause damage to neutral states. Because the effects of a nuclear explosion are uncontrollable, those requirements cannot be met. It is also prohibited to threaten actions having those consequences.

ICAN: Are countries required by law to eliminate their nuclear weapons?

JB: The nuclear Non-Proliferation Treaty (NPT) prohibits acquisition of nuclear weapons by the vast majority of states, and there is a universal obligation, declared by the International Court of Justice and based in Article VI of the NPT and other international law, to achieve their elimination through good-faith negotiation. It cannot be lawful to continue indefinitely to possess weapons that are unlawful to use or threaten to use, are already banned for most states and are subject to an obligation of elimination.

ICAN: Is force modernization at odds with the duty to disarm?

JB: Under a fundamental principle of international law, the obligation to negotiate nuclear disarmament set forth in the NPT and affirmed by the International Court of Justice must be implemented in good faith. Good faith means abiding by agreements in a manner true to their purposes and working sincerely and cooperatively to attain agreed objectives.

Modernization of nuclear forces and the supporting technical infrastructures undermines or renders impossible achievement of the objective of global elimination of nuclear arsenals. It stimulates qualitative nuclear arms racing, instead of marginalization of nuclear forces as they are reduced and eliminated.

ICAN: What if the only aim is to maintain existing military capabilities?

JB: The long time frame for planning and executing such modernization, on the order of several decades, and the substantial spending involved, erodes the credibility of arms control and disarmament commitments and measures, and diverts governmental resources into bolstering rather than transforming the status quo. What we need are disarmament infrastructures – well-resourced governmental agencies devoted to achieving the abolition of nuclear weapons – not nuclear weapons infrastructures.

ICAN: Can countries prohibit investments in nuclear weapons companies?

JB: Yes, they can and should. A model is provided by the Ethical Guidelines for the Norwegian Petroleum Fund, a governmental entity. The guidelines provide that funds should not be invested in companies that produce weapons that, through their normal use, may violate fundamental humanitarian principles. Nuclear weapons have been included among the covered weapons, and the fund has sold investments in certain companies that develop and produce them.

ICAN: Are banks generally aware of the illegality of nuclear weapons?

JB: No, but that’s because banks, like others, don’t want to think about it. Once you fulfil the basic responsibility owed by everyone to present and future generations of paying attention to the consequences of nuclear weapons, the conclusion is straightforward: nuclear weapons are inhumane, immoral, and illegal, and must be abolished.

What Legal Obligations Is My Country Subject To?

NPT Nuclear-Weapon States

These five nations – the United States, Russia, the United Kingdom, France and China – each possess nuclear arms. They are legally obliged, under Article VI of the Nuclear Non Proliferation Treaty (NPT), to pursue in good faith and conclude negotiations for the complete elimination of their nuclear forces. They are prohibited from engaging in activities (such as warhead modernization and the construction of new nuclear delivery vehicles) that would make this goal less likely or impossible to achieve.

NPT Non-Nuclear-Weapon States

Under Article II of the NPT, these 184 nations are prohibited from ever receiving, manufacturing or otherwise acquiring nuclear weapons. Many of the non-nuclear-weapon states parties to the NPT also belong to regional nuclear-weapon-free zones. Such zones, like the NPT, prohibit the possession and manufacture of nuclear weapons. Along with all other nations, they are obliged to pursue nuclear disarmament and refrain from doing anything that would make the achievement of that objective less likely or impossible.

States Not Parties to the NPT

These four nations – India, Israel, Pakistan and North Korea – possess nuclear weapons but are not subject to the requirements of the NPT, as they are not parties. Nonetheless, customary international law imposes on them the same obligation to disarm as is enshrined in Article VI of the NPT, according to the 1996 ruling of the International Court of Justice. Similarly, under customary international law, they may not engage in activities that would render achievement of nuclear disarmament less likely or impossible.

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written by

Australian director of the International Campaign to Abolish Nuclear Weapons
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