Federal “solutions” are bandied about by armchair constitutional designers, their purported benefits for Iraq or elsewhere debated on talk shows and in academic conferences. At times, the support for federalism seems based on its apparent middling position between unitary government and partition; it is a compromise. But is federalism feasible? Federation is not easy to pull off, and Daniel Ziblatt's book, written about two cases of state formation in the mid-nineteenth century, should be read by all who advocate federalism in transitioning states today because it provides us with a careful analysis of the potential for fractured states to embrace federal unification.

Anyone who thinks that constitutional drafters can effortlessly implement their vision of an ideal system will be disabused of this naïveté quickly upon reading Ziblatt's book, which makes plain that the alternatives available to constitutional drafters are limited by preconditions that they are powerless to alter. In particular, if the designers want federalism, they had better have in place flourishing constitutionalized and commercialized subunits. The author's thesis is developed as an explanation for the different paths taken by German and Italian unification in the mid-nineteeth century. In both, unifiers held a vision of federalism, but only in Germany did that vision become a reality.

Ziblatt takes on not just one ambitious, broad, bottom-of-it-all question, but two: 1) Why do nation-states form? and 2) Why do nation-states take on unitary or federal structures? In his analysis these two questions meld into one: Under what conditions can we expect federalism to be the outcome of the process of state formation? Federalism becomes a question not only of should we do it but also of can we do it, a feasibility reality-check giving it a leg up over the optimizing analyses of economists, who prescribe federalism based upon expected benefits rather than institutional fit.

Ziblatt takes the stance that in order to know if federalism is feasible you need to examine its preconditions, a fresh return to the question that William Riker took up in 1964 in Federalism: Origin, Operation, Significance. Riker's preconditions focused exclusively on military power and territorial ambition: The initiators of federalism want to expand but are not quite strong enough to take a neighboring state by force; those who acquiesce fear invasion by others and therefore are lacking in military strength. His paired hypotheses have long been demonstrated to be insufficient, and have generally been set aside as a curious product of Cold War thinking. Ziblatt revives the study of preconditions, but rather than looking at military power, he substitutes institutional capacity to get a theory of negotiating capacity that matches his cases better, and may be more broadly applicable today.

In Ziblatt's argument, the determination of a region's support for unification is a function of the region's size and the extent to which it is commercialized. The key insight is that for action (for or against), a regional government needs both means and motive. Commercialization provides the motive, while state size (as an indicator of capacity) provides the means. Large states are the movers; those that are highly commercialized are the initiators of unification, and those that are not commercialized are most likely to strongly resist unification. Small states split in support or dissent based on their degree of commercialization but do not organize movements on either side. The argument is crisply captured in a 2–by-2 table on page 25. The bottom line: Germany had sufficient subnational institutional development, and so therefore federalism was possible. In Italy, there were no significant subnational institutions, and so there was no federalism.

Those who like the transparency of a formally derived argument will not find it here. Also likely to ruffle some feathers is the usual difficulty of coding qualitative data. For example, institutional capacity is to be measured in three ways (p. 13): state rationalization, state institutionalization, and embeddedness of the state in society. But these enticing terms are left essentially undefined in Chapter 1. Instead, Ziblatt substitutes a shorthand: “constitutional, parliamentary, and administratively modernized” determines the capacity to negotiate and govern. These potential criticisms can be set aside because of the way that he chooses to build his case. It is clear that he has spent many long hours with archives, but rather than using them to set the stage for a tale of charisma and derring-do, he carefully assembles evidence of codifiable qualitative or quantitative data to facilitate an honest and compelling comparison between the German and Italian state-formation processes. Methodologically, Ziblatt's work is in the tradition of Robert Putnam: He focuses exclusively on interests and institutions, even when some might want more. The benefit of his focus is a tight argument.

Does he change my thinking? Yes, absolutely, and no. Yes: To understand the national institutions you need to understand the institutional capacity of its components, and rather than thinking of them in isolation, you need to evaluate them within the context of their cohorts. Ziblatt's careful research is compelling on this score. The data are not as sharply bifurcated as the argument, but are they ever? But we must bear in mind the limited focus of his work: He wants to explain the origins of federalism. He does not tackle its sustainability, the other necessary consideration in evaluating a federation's feasibility. Today, Italy and Germany are not as distinct as they were at founding: Germany has grown more centralized while Italy's process of decentralization is starting to feel federal in practice, if not in law. Their evolution raises questions about federalism's sustenance and also the emergence of a federal culture.

An interesting further research program, informed by Ziblatt's work, might examine how these elite ideas and existing institutional forms affect the public perception of their state. Can institutions grow a federal culture, and under what conditions? Public reaction to the institutions affects the institutional performance. People's reactions depend upon what they are used to. Can these public beliefs change, and if so, in response to what? Could this be a way for us to understand the eventual nature of both Italian and German states? With few exceptions, most analyses of institutions focus on the way that preexisting structures affect new structures. The medium in that transition might be public perception. To make better constitutional recommendations, we scholars of federalism and constitutional performance should turn our attention to belief evolution and cultural transformation.