A Theory of Regional Conflict Complexes

Abstract: Civil conflicts spill over to neighboring countries. This paper proposes a theory of the contagion of civil wars, emphasizing two main channels of diffusion of a conflict. First, weak territorial control facilitates the emergence of a regional market for war inputs in the "porous frontier." Second, refugees fleeing a conflict zone may unwittingly destabilize their host country. In both cases, the contagion effect is nonlinear and creates multiple equilibrium situations of regional complexes of civil conflicts. This helps explain observed patterns of regional clustering of conflict and state capacity, and raises identification issues in the measurement of the contagion effect. We also derive a positive spillover of civil wars: governments are sometimes in a position to avoid contagion by improving their institutions. Finally, we explore policy implications for military intervention, military and institutional cooperation, and the international coordination of refugee policy.