Unlike the theory of international trade and payments, theorizing on international relations or the international “system” is of fairly recent origin, has attracted relatively few scholars, and—in terms of achievement—is still in a rather underdeveloped stage. But there has in fact been important progress during the last twenty-five years, much of it along tentative, experimental, and not necessarily congruent lines. Nowadays there seems to be new interest in such theorizing and the Center of International Studies at Princeton University thought it useful to collect a reasonably representative sample of recent thinking and, toward this end, to call upon younger scholars in the field rather than on the established leaders, such as Harold Lasswell, Hans Morgenthau, Richard Snyder, Arnold Wolfers, and Quincy Wright.

There is a great demand for theories in international relations. The term “theory” has become so honorific that hypotheses, statements of fact, and intuitive guesses are often dressed up as theories. In part this longing for theory can be ascribed to a desire for the status of a “hard science” like physics, since the “hard sciences” are often viewed by laymen as the theoretical sciences par excellence. They have displayed their power in revealing the secrets of nature and, when applied to the affairs of men, have achieved notable practical successes like the construction of the atomic bomb.

On the whole this demand for theory is probably good. We cannot reason without generalization and, where matters are complex, the web of reasoning logically takes the form of a theory. Most historical investigations and case studies employ theories inexplicitly—often in the belief that the generalizations follow from the straightforward presentation of “purely factual” material. There is usually no recognition that interpretations of factual material can always be presented in a form isomorphic with theories from the sciences of economics, psychology, sociology, and so forth.

How far may we hope to go in theorizing about international affairs? That question is at the center of this article, which consists of several more or less eclectic stabs at the problem.

I shall be writing as though some theory of power politics were the only possible candidate for being the theory of international relations. Let that be regarded as an act of methodological faith—certainly I can think of no scientific demonstration of it, and I would rather leave the philosophy of the matter for another occasion. There are a number of stock objections against any general theory of international relations oriented towards power politics, and these I shall try to rebut, chiefly by extending and correcting my own previous efforts in the genre. I shall then introduce objections of a rather more abstract sort, and, again from my own previous work, I shall try to show that the difficulties which these latter present are indeed formidable. But I hope it will be understood that neither kind of objection need be relevant to meories of international relations other than those built around the concepts of force, power, and security.

Games have been used in the study of international politics; if they were not so demanding of time and energy, they would probably be used more. A Berlin crisis, or a busy day in the life of the United Nations, lends itself to this procedure. Participants usually represent “countries” and they may be encouraged to play the “role” of the country, acting as they believe the country would act, or they may be encouraged to behave in the game as they believe the country ought to behave in its own interest. The game may be organized for research, the participants being scholars and policy analysts; or it may be organized as training, to give students vicarious experience in the complexities of international politics.

Among all the social sciences, the art of model building is perhaps best developed in economics.Models or theories are conceptualizations of and abstractions from reality; they rely intrinsically on ldquo;if-thenrdquo;statements and should lead to testable propositions if they are to be of any use at all.

It would be difficult to give a brief description of all the important characteristics of economic models, for there are numerous types, designed to describe or explain completely different aspects of economic reality. Most of them contain as essential ingredients some statements about the technical environment (e.g., marginal cost curves rise after a certain point) and some statements about human motivation (e.g., the entrepreneur desires to maximize profits; the consumer maximizes utility).The models themselves can have either descriptive or normative use. The Keynesian model or theory “explains” the factors diat cause the level of national income to be what it is and allows one to deduce the direction of change in national income resulting from changes in the parameters. The usefulness of such a descriptive model is determined by whether or not its conclusions are testable propositions. Normative models, most frequently encountered in economics in welfare economics and in operations research, also utilize statements about environment and motivations but do not pretend to predict; infact they merely prescribe. The test of the usefulness of such normative models is whether ornot their prescriptions are at least in principle imple—mentable.

In any area of scholarly inquiry, there are always several ways in which the phenomena under study may be sorted and arranged for purposes of systemic analysis. Whether in the physical or social sciences, the observer may choose to focus upon the parts or upon the whole, upon the components or upon the system. He may, for example, choose between the flowers or the garden, the rocks or the quarry, the trees or the forest, the houses or the neighborhood, the cars or the traffic jam, the delinquents or the gang, die legislators or the legislative, and so on. Whether he selects the micro- or macro-level of analysis is ostensibly a mere matter of methodological or conceptual convenience. Yet the choice often turns out to be quite difficult, and may well become a central issue within the discipline concerned. The complexity and significance of these level-of-analysis decisions are readily suggested by the long-standing controversies between social psychology and sociology, personality-oriented and culture-oriented anthropology, or micro- and macro-economics, to mention but a few. In the vernacular of general systems theory, the observer is always confronted with a system, its sub-systems, and their respective environments, and while he may choose as his system any cluster of phenomena from the most minute organism to the universe itself, such choice cannot be merely a function of whim or caprice, habit or familiarity. The responsible scholar must be prepared to evaluate the relative utility—conceptual and methodological—of the various alternatives open to him, and to appraise the manifold implications of the level of analysis finally selected. So it is with international relations.

It is a truism that all action within the international system can be reduced to the action of individuals. It is also true, however, that international relations cannot be adequately understood in terms of individual attitudes and behaviors. Models of the international system usually deal with larger units, nation-states, as prime actors. To what extent can such models give us adequate explanations of international relations without some built-in variables to deal with individual decision-making?

It may be that some processes in international relations can be adequately explained on the level of social structure without explicit consideration of the personality, predispositions, attitudes, and behavior of the individual decision-maker. In that case, the introduction of variables dealing with individual behavior would complicate the model without commensurate payoff in terms of increased understanding and prediction. This would be true if the impact of individual decision-making on the behavior of nations in their relations with other nations were slight, or if the impact varied randomly (because, for instance, of idiosyncratic factors) among the population of international events that one was trying to explain. If, on the other hand, models of the international system that either ignore or make grossly simplifying assumptions about individual decision-making can explain international relations only very imperfectly, it may well be worth the additional effort to build variables about individual decision-making into them.

Ever since the invention of the steam engine in the eighteenth century, men have reflected upon the profound transformations being wrought in their societies by what soon came to be called the Industrial Revolution. In their own fields, historians, economists, sociologists, military specialists, and Marxist philosophers have all traced the effects of industrialization, and some of them—particularly those interested in and aroused by war—have perceived the implications of these changes for international relations. Priority in this respect seems to belong to Auguste Comte, the founder of modern sociology, for devising the first analytical-historical model of the industrial society—one moreover that explicitly, though not always convincingly, pointed to the international repercussions of industrialism. In an essay first published in 1822, Comte drew a distinction betwelen two types (or models) of civilization: the Theological and Military, and the Scientific and Industrial (there also was a third, transitional—as he called it, “mongrel””type, the Metaphysical and Juridical). Comte's first model is notable for the predominance of military activities: “Society makes conquest its one permanent aim.” War makes it possible to found larger societies. In the transitional stage, he observed, “The two aims of activity, conquest and production, advance pari passu. Industry is at first favoured and protected as a military resource. Later its importance augments, and finally war is regarded and systematically pursued as a means of favouring industry.” But, in the last model, “industry has become predominant. All the special relations have gradually established themselves upon industrial bases. Society, taken collectively, tends to organize itself in the same manner,” renounces conquest and war, and makes production “its only and constant aim.”

Conventional theories of international relations assume, implicitly, the model of an “inter-state system.” According to this model, individually states possess a set of characteristics which differ fundamentally from the characteristics of a system of those states interacting with each other. On this basis we can construct theories about the behavior of component states in the system, and more general propositions about the nature of the inter-state system viewed as a whole. Some of the difficulties of this model will be noted here, and an alternative model proposed.

Before pointing to these difficulties, however, we need a clear image of the inter-state model. A classic formulation is contained in a speech given by former Secretary of State John Foster Dulles at a meeting of the American Society for International Law. In it Mr. Dulles identified six characteristics of the nation-state: (1) laws which “reflect the moral judgment of the community”; (2) political machinery to revise these laws as needed; (3) an executive body able to administer the laws; (4) judicial machinery to settle disputes in accord with the laws; (5) superior force to deter violence by enforcing the law upon those who defy it; and (6) sufficient well-being so that people are not driven by desperation to ways of violence. The international system, Mr. Dulles pointed out, in large part lacks these characteristics. He went on to assess the limited success of attempts, ranging from the League of Nations and Kellogg-Briand Pact through the United Nations, to create such a “state system” or “order” at the international level. Mr. Dulles sadly reported that, despite notable progress in the development of international law and judicial machinery, the desired international order does not, as yet, exist.

Accounts of the acute crises of international politics occupy a substantial place in the diplomatic history of the past hundred years. These compounded events have been interpreted as manifestations of international rivalries among the Great Powers. Intermittently, they have drawn intense public attention and have generated heavy anxieties over the possibility that they may lead into general warfare. After the fact, they have become subjects of historical reconstruction, with students and commentators attempting to describe “what really happened.” Thus, both scholarly and popular interest has persisted in the “inside stories” of the several crises belonging to three historical periods: from 1870 to World War I, the interwar period, and the era since World War II.

There is, consequently, a large descriptive literature of the crises, mainly connected with the diplomacy of opposing coalitions and of interstate conflicts during these three periods. The depth and quality of this literature vary greatly, most often according to the recency of the events and the amount of available and relevant historical documentation. The Moroccan crisis of 1905 and the circumstances of the Anschluss of 1936 are, quite naturally, better known and more firmly established factually than the inner details of the Suez crisis of 1956. However, the accumulated knowledge of the series of crises of the post-World War II period, uncertain and impressionistic as it still is, has a great deal to do with our understanding of current international affairs. Take away the facts and meanings commonly associated with the crises of Berlin, Korea, Indochina, Suez, Quemoy, the Congo, and Laos and, obviously, the usual estimates of the scope, intensity, and workings of the Cold War will greatly change. Despite this fact, acute crises have not often been made the focus either of theorizing or of intensive analytic research. Students of international relations have not found it important or necessary to consider these events as if they constituted a significant class of phenomena in the international field. The reasons for passing over the acute international crisis as a focus of explanation are worth consideration.

The purpose of this essay is twofold. First, it proposes to undertake, in introductory form, one of the many tasks a historical sociology of international relations could perform: the comparative study of one of those relations which appear in almost any international system, i.e., international law. Secondly, this essay will try to present the rudimentary outlines of a theory of international law which might be called sociological or functional.

International law is one of the aspects of international politics which reflect most sharply the essential differences between domestic and world affairs. Many traditional distinctions tend to disappear, owing to an “international civil war” which projects what are primarily domestic institutions (such as parliaments and pressure groups) into world politics, and injects world-wide ideological clashes into domestic affairs. International law, like its Siamese twin and enemy, war, remains a crystallization of all that keeps world politics sui generis. If theory is to be primarily concerned with the distinctive features of systems rather than wim the search for regularities, international law becomes a most useful approach to international politics.