The Permanent Missions of New Zealand and Switzerland to the United Nations sponsored a First Committee side event on the legal status of nuclear weapons at the UN’s New York Headquarters on October 18, featuring three prominent international lawyers. It was the contention of the panel that existing international law prohibits nuclear weapons implicitly. But an explicit convention against nuclear weapons should be pursued, Prof. Daniel Thuerer, Prof. Roger S. Clark, and Prof. Andrew Clapham concluded.
“Is the threat or use of nuclear weapons in any circumstances permitted by international law?” – The UN General Assembly in Resolution A/RES/49/75 [K] sought the opinion of the International Court of Justice on this matter nineteen years ago. While the Court in its response argued that the threat or use of nuclear weapons is generally not compatible with the principles and rules of international law, the judges could not conclude definitely whether nuclear weapons may be used legally under very exceptional circumstances of self-defense, in which the very survival of a State is at stake. The Advisory Opinion, rendered in 1996, was front and centre of the arguments delivered by the three experts at the side event.
Prof. Daniel Thuerer, Professor Emeritus of International Law at University of Zurich, said the Court had “mixed up two categories of law which are supposed to be strictly apart”: The law relating to the use of force, or ‘jus ad bellum,’ and the law of armed conflict, or ‘jus in bello.’ According to Thuerer, one important reason to keep both regimes separate is the difficulty of deciding which party’s use of force is ‘just’ and which is not. But even if this distinction were possible, it would still be absurd to make the protection of civilians, who very often have no say in the decision to go to war, dependent on whether their government’s decision to fight war was ‘just,’ he argued. Humanitarian law was established to serve the humanitarian needs of all individuals affected by armed conflict – independently of which side they are on, he pointed out.
“With its Advisory Opinion, the International Court of Justice undercut the legitimacy of nuclear weapons,” Prof. Roger Clark of the Rutgers School of Law said. The threat or use of nuclear weapons is a crime of aggression, he argued. “Whether we have a crime of aggression or not is indiscriminate of the kinds of weapons used – its definition is weapons neutral.” With the threat or use of nuclear weapons, two important criteria – ‘intent’ and ‘knowledge’ – would be satisfied, he added.
For a case of self defense to be lawful, the principles of international humanitarian law must be respected, Prof. Andrew Clapham, Professor of Public International Law at the Graduate Institute of International and Development Studies in Geneva, argued. “The Court made it very clear that there were two conditions that need to be satisfied: the dual conditions of necessity and proportionality.” Necessity, he stressed, means that a State may only use force if all other means of self-defense have been exhausted, and only to the extent necessary to end an ongoing attack or avert another imminent one. “It cannot be simply retaliatory. If there is another way to repel the attack, force must not be used.” Proportionality is a question of using only sufficient force as is needed for repelling the attack, and does not relate to symmetry between the damage done in attack and response, he underlined. “It is not relevant, what was done to you.”
All panelists agreed that while international law as it exists today can be interpreted as prohibiting nuclear weapons, a formal nuclear weapons convention, whose absence Prof. Thuerer described as “the most alarming gap in the framework international humanitarian law,” should be established. “We need a convention against nuclear weapons that prohibits their production, use, and threat and provides for verification and enforcement of their destruction,” Prof. Thuerer said. “It is forbidden to use poisoned arrows, but not nuclear weapons,” Prof. Clark added, pointing at what the experts perceive as a significant shortcoming in the current legal status of nuclear weapons.
Article and photographs by Elias Oberkirch