Military Intervention in Civil Wars: Individual-Level Explanation of Leaders’ Decisions

Why are some national leaders more likely to intervene in a civil war than others? In this paper, I suggest that prior military service and combat experience can influence leaders’ risk perception by altering what they expect the result of their (in)action to be, as well as making militaristic means more mentally accessible, creating a militaristic heuristic for judgments. Analyzing national leaders from 1875 to 2004, I find that 1) leaders who have a military service background are about 3.86 percent more likely to engage in third-party intervention compared to those without; 2) leaders who were deployed in combat are around 4.53 percent more likely to intervene than those who either do not have any military experience at all or have military service experience but were never deployed; and 3) leaders’ military service experience without deployment in combat shows almost no impact especially when the standard error was taken into consideration. By examining how individual leaders’ experiences impact third-party intervention, this study aims to contribute to the agent-structure debate in IR and the debate on political decision-makers and their personal backgrounds.