Published online by Cambridge University Press: 24 February 2017
This article explains the empirical connection between dyadic capability differences and international conflict as a consequence of how, when, and where states enter the international system. State capabilities are largely static, and, since states enter the system in geographic clusters, the processes of state maturation affect contiguous and regionally proximate states similarly. This makes dyadic capability differences static as well. The lack of change in capability differences over time suggests that the parity-conflict relationship is largely a product of the factors associated with state system entry. Indeed, as I demonstrate, several different proxies for the conditions of state system entry separately eliminate any statistical relationship between parity and militarized dispute onset, 1816–2001. I also find no relationship between parity and the wars that have occurred during that same time period. These results have a number of implications for the role of power and capabilities in explaining international conflict.