Deborah Boucoyannis has published a thought-provoking article in this month’s Perspectives on Politics in which she argues that neo-realism is actually most consistent with classical liberalism, and in which she articulates a new way of distinguishing realist and liberal IR theory.

If her argument is correct, most of us will have to completely rethink how we teach the two theories in our introductory classes.

In particular, she argues that “the balance of power is a liberal prediction…” (underlying the checks and balances systems of liberal constitutionalism as well as the logic of economic liberalism) and by contrast, realism is “better defined as the theory predicting that balances will not occur; that concentrations of power will form, thus destabilizing the system and threatening the security of individual units.”

There are so many fascinating parts of this article I can’t name them all. Boucoyannis’s done us an an enormous service by disaggregating classical and contemporary realism and liberalism, and sorting out the contradictions between IR liberalism and economic and constitutionalism liberalism. (That alone will help me greatly as I attempt each semester to get my policy students to forget everything they’ve ever learned about what the term means in domestic politics.) And her disassociation of Realism and state-centrism is particularly interesting.

But I see two weaknesses in the argument. First, Boucoyannis seems to confuse prediction with prescription in her genealogy of these two theories and her description of their variations. She is trying to redefine them according to what they predict about balancing. But it seems to me that the distinction between IR liberalism and IR realism is not their predictions about that, but rather their predictions about the consequences of balancing, and therefore their prescriptions for how states should act in order to avoid great power war.

Classical realism does not necessarily predict balancing. What it predicts is great power war in the absence of a balance; therefore it prescribes efficient balancing. Liberal IR does not necessarily eschew the balance of power as a prediction. But it predicts that balancing is dangerous rather than stabilizing and therefore it prescribes changes in the nature of the system (international institutions), and the nature of the units (democratic, capitalist, nation-states). So in some ways, I feel like the argument is spot on and very illuminating, but also not that revolutionary.

Second, the similarities Boucoyannis draws with domestic political theories and IR theory seem spurious. In short, her argument seems to rest on a constant confusion of the units of analysis. So while she talks about the constitutionalism inherent in domestic “balance of power” politics among factions, she makes no reference to what would seem to be the international corrolary – interstate organizations, the study of which is a staple of Wilsonian liberal IR theory.

She claims that the only institutional form that matters at the international level is the structural pattern of efficient alliance-building (which is what Realists have been said to predict). But, she then distinguishes this from Realism by distinguishing alliance-building per se from realpolitik, meaning “policy determined by practical, rather than moral or ideological, considerations.” So, does this mean that liberal alliance-building would include alliances formed on the basis of morals or ideologies (e.g. a club of democracies) rather than on the basis of the distribution of power per se? Then this would not seem, to me, to be power-balancing at all.

In the end what Boucoyannis seems to be doing is situating defensive Realism as Liberalism, and offensive Realism as Realism. This is interesting, but of course it completely evacuates the study of international law and institutions from Liberal IR theory. Then again, perhaps social constructivists could simply take up that banner.