What Makes a World War? Economic Linkages and the Distribution of Power

• In Event: Political Economy of War: Theories and Implications

Abstract

Why do some conflicts escalate to large-scale war while others stay contained? I provide a formal model of conflict that considers an international system of many countries, all of whom are located on an economic network and endowed with military capacity. When given an opportunity, a country may attack an adversary of their choosing and, if war breaks out between them, the remaining countries choose whether to join the fight. I demonstrate how changes in the distribution of power and globalization can drive both increases and decreases in the expected size of conflicts, motivating quantitative analysis. Taking the theoretical model to data on international disputes, I estimate deep structural parameters governing country preferences. The structural approach helps mitigate problems related to data limitations, identification, and out-of-sample extrapolation. The results of the model inform on what characteristics of an international system foster large-scale conflict. Counterfactual analysis is employed to both assess conventional claims about historical global wars and evaluate the necessary conditions for global war in contemporary times.

Author

• Joseph Ruggiero, Stanford University