Reconceptualizing Anarchy:

How can the understandings of world historians about the critical changes in the international system be brought into harmony with the way IR theorists think about system change? One of the main obstacles to this task is Waltz's conception of structure, particularly his much criticized elimination of functional differentiation of units in anarchy. Until this flaw is corrected, the theory remains fundamentally incoherent, having misguidedly sacrificed rigour for parsimony. Waltz cannot defend both his exclusive anarchy-hierarchy dyad as the first tier of structure, and the closure of the second tier, against attacks by Ruggie, Watson and Deudney. While the anarchy-hierarchy formulation of deep structure is defensible, the closure of the second tier is not. Both on theoretical and historical grounds, anarchy is compatible with differentiation of units — there is more than one type of anarchic international system. Neorealism therefore gives a partial and Eurocentric view of international systems, and cannot sustain its transhistorical claim. With carefully specified definitions for functional and structural differentiation of units, it is possible to retain a coherent, and still quite parsimonious, theory that is capable of encompassing all of the known manifestations of international systems. Only with such modifications is it possible to address the significant systemic transformations both ancient and modern that now pass unnoticed through the broad mesh of the neorealist net.