The Power of a Ban: Outlawing Nuclear Weapons Practices

The Treaty on the Prohibition of Nuclear Weapons (TPNW) that will enter into force in January 2021 bans nuclear weapons by outlawing a number of practices. These include possessing nuclear weapons, developing, testing, stockpiling, transferring, using, threatening to use, encouraging and stationing them. To understand why the ban on nuclear weapons is a watershed moment in history that will bring about a psychological shift in how people think about nuclear weapons, we have to understand what it means to outlaw something.

Outlawing a practice means that it is deemed unacceptable by a community, which then creates law to put an end to (or abolish) the practice by making it illegal and illegitimate. This does not mean that no one will ever engage in the practice again, but when they do, they will be on the wrong side of the law (or “outside” the law). When a person is outlawed, he/she is no longer entitled to the protection or benefits provided by the laws of that community. Herein lies the power of the Nuclear Ban. It changes the incentives for those who are engaging or thinking of engaging in the practices that make nuclear weapons (and by extension nuclear war and accidents) possible. It creates consequences that will be on the minds, not only of state leaders, but also of individuals along the decision-making, support and operational chain of nuclear weapons. These include nuclear scientists, academics, politicians, business people, engineers, military commanders, and others that assist in nuclear weapons practices. 

To begin with, most individuals and even states as communities of individuals want to be on the right side of the law and do what is morally acceptable. The moral suasion of the humanitarian approach on which the Nuclear Ban is built provides the foundation to stigmatise practices that make nuclear weapons possible, as well as those who engage in those practices. However, the TPNW’s impact goes beyond moral suasion by having material consequences for those who take part in practices that make nuclear weapons possible. Whatever is acquired as a result of outlawed practices can be confiscated, destroyed or lost in the future. A state which invests billions in producing or modernising nuclear weapons may be condemned and sanctioned by the international community and end up having to give up their nuclear weapons eventually. A company that invests in nuclear weapons technology may be sued for profiteering from illegal and immoral activities. A nuclear weapons engineer may lose a chosen career and a reputation. 

The TPNW’s power to change incentives for states and individuals goes even further than material and reputational risks. It has punitive consequences for all involved. Individuals may be tried in international courts or by tribunals when they engage in nuclear weapons practices. We must remember that the Nuclear Ban fits into a system of international law. The practices it prohibits are therefore judged not just in the context of the TPNW, but in the context of complimentary branches of international law. These branches include the law of armed conflict that requires distinction between military and civilians in conflict, the proportional use of force, and the limitation of suffering, as well as human rights law that protects the right to life and a safe environment. The TPNW bans weapons on the humanitarian grounds already codified in these branches of law.

The impact of international law that banned two other international practices on humanitarian grounds, namely slavery and wars of aggression, illustrates the power of a ban. Once commonplace and legitimate, slavery and wars of aggression have been turned into aberrations. More specific examples exist of how international law functions in this area. In 1961 Adolf Eichmann was tried in Israel for his role in the holocaust, after being captured in Argentina by Israeli special agents. His capture and trial were justified under the guiding principle established by law that abolished slavery and piracy, namely that enemies of humanity can be captured and tried by any nation. Eichmann was found guilty and executed. As an outlaw (an enemy of humanity), he could not claim protection under any law. Both the Nuremberg and the Tokyo tribunals, in addition to charges of wartime atrocities, tried individuals for crimes against peace drawing on the 1928 Kellogg-Briand Treaty that outlaws wars of aggression. Russia’s annexation of Crimea has incurred sanctions and international condemnation for Russia and, importantly, non-recognition of its sovereignty over Crimea, because it was acquired by an outlawed practice – a war of conquest. 

These legal precedents should induce powerful disincentives for individuals and states, even major powers, to engage in the practices that the TPNW outlaws. It may seem unthinkable now that the leaders of the United States and Russia, or those individuals, who operate nuclear weapons and think up nuclear strategy, will end up being tried for crimes of nuclear weapons practices in The Hague. But, let’s not forget that Germany was a major power prior to the end of World War II. As the Nazis learned, today’s untouchables can be tomorrow’s defeated having to face the law. Imagine a state and its leaders responsible for a nuclear war, intended or not, and the unthinkable humanitarian disaster that results from it. In the aftermath of such an event, public opinion will not accept the defence that nuclear deterrence justified the risk of such horror and neither will the courts. 

It is true that at this point the TPNW is likely only binding on the states that have joined the treaty. However, the power of the Nuclear Ban can grow over time to become customary international law, general practice accepted as law and binding on everyone, everywhere. How does this work? Customary international law concerns patterns of practice, as well as patterns of legal expectation, what can also be deemed the acceptance of something as law. The nuclear weapon states have been at pains to refute that the TPNW contributes to customary international law against nuclear weapons. But, here’s the catch: it is not just about what official state elites have to say. It is about what human beings in general think about nuclear weapons that counts towards the development of customary international law. Paust argues: “…a particular nation-state might disagree whether a particular norm is customary and might even violate such a norm, but it would still be bound if the norm is supported by patterns of generally shared legal expectation and conforming behavior extant in the community.”

The foundations to make the Nuclear Ban binding on those states that have not acceded to the TPNW have indeed already been laid. The norm against nuclear weapons is concrete in the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) of 1970, a treaty that is close to universal. Unfortunately, the NPT has a legal loophole that allows the nuclear weapons states to continue postponing nuclear disarmament indefinitely (since the treaty was extended indefinitely in 1995). It does not set a date for states that have tested nuclear weapons by 1967 to negotiate nuclear disarmament, even though the treaty makes such negotiations a binding obligation in article 6. The nuclear weapon states have disingenuously interpreted the NPT as therefore giving them a sovereign right to possess nuclear weapons and to control them on their own terms.  Four states that are not members of the NPT have followed the nuclear weapon states’ example and acquired nuclear weapons. These practices and interpretation work against the Nuclear Ban and its customary law status. The only way I see for states that are serious about nuclear abolition to invalidate this interpretation of the NPT, reclaim its original intent and strengthen the customary law status of the Nuclear Ban is to withdraw from the NPT and join the TPNW. Withdrawal will be legitimately based on the grounds that the nuclear weapon states are in breach of article 6. 

The Nuclear Ban’s customary law status is also built on the many times that world leaders have publicly deplored nuclear weapons, like Reagan and Gorbachev did at the Reykjavic Summit in 1986. The times that leaders could have used nuclear weapons, but didn’t, because of the humanitarian consequences (the nuclear taboo), is clearly a pattern of state behaviour against the use of nuclear weapons. 

The TPNW is an instrument around which activist states and civil society is doing the political work necessary to strengthen the legal case that nuclear weapons practices are generally unacceptable to humanity at large. The recent open letter by 56 former presidents, prime ministers, foreign ministers and defence ministers from 20 NATO member states, as well as Japan and South Korea, calling on current leaders to join the TPNW, is an example of this work.