Why don’t democracies fight each other? The role of territorial issues

Why don't democracies fight each other? Since discovering this empirical regularity, scholars have assumed that the answer must lie with regime type (i.e. democracy). Our paper provides and tests an alternative explanation: the territorial explanation of war, which stresses grievances and argues that territorial issues incentivize states to resort to war more often than disagreements over other, non-territorial issues. We show that democracies do not generally have territorial militarized interstate disputes (MIDs) or the territorial claims that would produce territorial MIDs. Democracies are peaceful because they lack the most dangerous grievances in the international system.