The principal aim of this paper is to relate the normative structure of international law to the underlying patterns of political behavior that have characterized the modern state system. The political constraint upon the normative structure of the law is only one of many; there are also economic, social, and ethical constraints, among others. Nonetheless, it provides many insights into the changing substantive content of the law and also illustrates the way in which theory helps to provide an understanding of subject matter.

A systematic study of the structure of the international society has been attempted elsewhere by one of the authors. Two different models of international systems delineated there have particular relevance to the present topic. These are the “balance of power” system, a model of the international politics of the eighteenth and nineteenth centuries, and the “loose bipolar” system, a model of present-day international politics. The two models, though no doubt less complex than the actual patterns of action, suffice to demonstrate important differences in system structure and behavior that can be related to normative standards.