The Physics of Statecraft: Technology, Terrain, and the Territorialization of Modern States 1

While variation in the power and size of states has long been recognized as one of the central drivers of geopolitical behavior, few studies have directly addressed the question of how and why different states came to be the sizes they did. The most prominent formal contributions to this question, based in a logic of voluntary optimization, fail to account for some of the most fundamental patterns observed in empirical data on state sizes, including the fact that territorial sizes are consistently lognormally distributed. In contrast, we develop an ecological model of coercive competition, which seeks to capture both the positive feedback dynamics inherent in states' pursuit of territorial expansion, and the physical constraints of projecting power over long distances. Moreover, we show that the empirical predictions derived from this model are in strong agreement, both qualitatively and quantitatively, with real distributions of state sizes observed over the period 1500 AD to 1998 AD.