Space-Time Granger Analysis of the War in Iraq: A Study of Coalition and Insurgent Action-Reaction

We investigate insurgent-coalition interaction using the WikiLeaks dataset of Iraq war logs 2004-2009. After a review of existing theoretical interventions on the dynamics of insurgency and presenting a baseline model of violent events, we test a conceptual model of reciprocity using an innovative space-time Granger causality technique. Our estimation procedure retains predicted probabilities of reaction in response to a previous opponent's action across different temporal and spatial configurations in Iraq and in Baghdad. Our conclusions about conflict in Iraq are based on these profiles of risk-what we call space-time signatures. We find strong evidence of tit-for-tat associations between coalition/Iraq forces on one side and insurgents/militants on the other. Specifically, we find that the action-reaction association varies strongly by majority ethnic region across Iraq and in Baghdad, by urban and nonurban location, and within Sunni-dominated areas, by district income. While violence is strongly temporally dependent in the same location, the effect of distance varies significantly across the different subsets of the Iraq data.