Roads and the diffusion of insurgent violence

Abstract

How does insurgency spread? Existing research on the diffusion of violence at the local level of civil war tends to under-specify the theoretical mechanisms by which conflict can be expanded, relocated or sustained, and overlooks the real-world logistical constraints that combatants face on a daily basis. This paper attempts to address both problems by taking a closer look at the role of road networks in the diffusion of insurgent activity. By explicating the logic of diffusion in a simple epidemic model and exploiting new disaggregated data on violence and road networks in the North Caucasus, this analysis challenges the conventional view that insurgent logistics are either self-sufficient or highly flexible. Roads shape the costs of sustaining and expanding operations, which facilitates the transmission of violence to new locations, but can also intensify competition for limited military resources between nearby battlefronts. At the local level, this dynamic makes the relocation of insurgent activity more likely than its expansion. Methodologically, this paper demonstrates that a failure to account for logistical constraints in the empirical study of civil war can underestimate costs of diffusion and overpredict the transmissibility of violence between neighboring locations. The use of road network distances can yield more conservative inferences and more accurate predictions of how violence spreads.