Nuclear weapons have—or rather should have—an impact on almost every field of international relations and international law. Physicists have been aware of this from the very moment it was clear that atomic energy could be used as a weapon. Arthur Holly Compton—to mention one—wrote: “That man shall learn humanity is the condition of survival in the atomic age. He cannot live with the new forces at his disposal without making important adjustments.” 1
In a Memorial Lecture, given at Washington University in honor of Arthur Compton, I tried to spell out some of these necessary adjustments: the limitation of national sovereignty; the ceiling of affluence; a New International Economic Order; the restriction of individual and state liberty in the pursuit of economic prosperity; and, no less important, the limitation of the national freedom of the employment and possession of arms. 2
The nuclear impact on international law is very broad indeed, too broad to be dealt with in this essay. I will restrict my observations to three fields of international law directly related with nuclear weapons: the jus ad bellum, the jus in bello, and the international law of arms control and disarmament.
The jus ad bellum concerns the right of a state to start war. The right of a sovereign state to use its armed power in promotion or defense of its interests was recognized by positive international law early in this century. Vague notions concerning the doctrine of just war did exist, but it was exclusively the state itself which decided whether it was entitled to go to war.
* Professor Emeritus of International Law and Polemology, University of Groningen; former Netherlands Judge on the International Military Tribunal for the Far East, Tokyo, 1946-48.