How Nuclear, Chemical, and Biological Weapons Influence War and Proxy War

• In Event: Causes and Conduct of Proxy Warfare

Abstract

Do Weapons of Mass Destruction (WMDs) influence the likelihood of interstate conflict and, if so, how and under what conditions do they do so? Does the possession of WMD increase the likelihood of limited and proxy warfare, while decreasing the chances of major war? Previous literature has focused almost exclusively on nuclear weapons when addressing this question, and large-n empirical tests of nuclear weapons have themselves found inconsistent evidence for key theories such as the stability-instability paradox. We investigate the relationship between WMD possession and interstate conflict through a large-n cross-conflict statistical analysis on the relationship between various types of WMD against multiple types of interstate conflict, building on recent literature with two innovations. First, we provide the first empirical tests of the relationship between not only nuclear weapons and interstate conflict, but also of chemical and biological weapons (CBWs). We find that states possessing CBWs are significantly more likely to engage in major war and limited conflict and that these dynamics are largely driven by CBW possession both emboldening states to initiate more conflicts and other states increasingly targeting them with attacks. Second, we expand the range of interstate conflicts by adding an indicator for proxy war, a prominent form of conflict that is systematically under-analyzed in security studies scholarship. We find that all types of WMD are associated with a significant increase in proxy war, especially dyads consisting of two nuclear armed states.

Authors

• David Logan, Princeton University

• Kyle Atwell