From international system to international society: structural realism and regime theory meet the English school

The idea of international society is an essential element in the study of international relations. International society is the core concept of the English school and has not yet been systematically integrated with American-originated structural realism and regime theory. This article brings together these three bodies of theory and shows how they complement and strengthen each other. It uses structural realism to show that international society is, like balance of power, a natural product of anarchic international relations and not, as some in the English school assume, only a result of exceptional historical circumstances. This line of analysis establishes definitional criteria for international society that enable a clear boundary to be drawn between international systems with and without international societies. It also shows how state-based international society relates to individual-based world society and supports an argument that in advanced systems, this relationship becomes complementary, not contradictory. The resulting theoretical synthesis provides an essential historical and political-legal foundation for regime theory, showing that international society is both the intellectual forebear and the necessary condition for the development of regimes. Connection strengthens all three bodies of theory and opens up useful channels that connect realist and liberal thinking. One result is that international society can be used both to conceptualize the complexities of a contemporary global international system, with its network of regimes ordered in terms of concentric circles, and to sketch out a policy-relevant research agenda for understanding it.