American Divorce: The Folly of a Red State and Blue State Divorce. 2025. Oxford University Press.

There is a growing interest in a national divorce between Red State America and Blue State America. Proponents of secession make three arguments: (1) That the two sides have irreconcilable differences; (2) That secession is a legal right; and (3) That smaller political units are better. I contend that these arguments are not only incorrect, but that secession is the wrong solution to the problem of polarization. Red and Blue America are not neatly sorted and geographically concentrated. Splitting the two parts would require a dangerous unmixing of the population. Rather than focus on national divorce as a solution, the better course of action is to seek common ground. My aim is to disabuse readers of the belief that secession will fix America’s problems.

 

Before Colonization: Nonwestern States and Systems in the Nineteenth Century. 2025. Columbia University Press, Series on International Order and Politics (with Charles Butcher).

How many independent states and state systems existed in the 19th century? How were they structured and what was their fate? We make three core contributions in the book. First, we catalogue the number of independent states since 1816, and we detail the regional patterns in state birth and state death. Indeed, we document quantitatively the large number of states that were extinguished as a consequence of European colonialism and the global enclosure. Second, we develop a theoretical and conceptual framework for comparing state systems, and show variation across four regions: East Asia, South Asia, maritime Southeast Asia, and West Africa. Third, we examine the effects that war, trade, and interaction capacity have on state formation.