Hans Kelsen on International Law

Kelsen's monistic theory of law, according to which international and municipal law have the same subject-matter, paved the way for the dominant contemporary doctrine: international law can encompass every aspect of human life which warrants international legal protection of human rights. Kelsen's doctrine of the identification of law and state held the legal order of the modern state to be the pattern of every legal system. Since, moreover, he considered physical coercion to be the very requisite of a legal normative order, Kelsen was bound to look for such a coercive element in the international order and found it in war. The experience of World War Two led Kelsen to develop the doctrine of the 'just war' (bellum lustum) as the appropriate sanction for violations of international norms, a theory which is hard to reconcile with his condemnation of every form of natural law. Kelsen s narrow definition of law prevented him from assessing the true nature of normative systems which do not fall within the state-based definition. Such systems may rely on non-physical forms of coercion, forms which are also available, as this article argues, to the International order.