What keeps the peace among Democracies?

Politicians and scholars have long accepted the notion that democracies are less likely to go to war against each other, yet there remains questions as to the reasons why. In a new Harvard Kennedy School Faculty Research Working Paper, “Information, Popular Constraint, and the Democratic Peace,” co-authored by Professor Matthew Baum, an argument is made that the political systems themselves are only one contributing factor accounting for the rapport amongst fellow democratic nations.

“Our research represents a first step in helping policymakers determine what it is about democracy that matters in inter-state conflict behavior, thereby hopefully allowing them to refine the policies they promote abroad,” writes Baum. “Emphasizing aspects of democracy that are likely to actually lead to a reduction in interstate war, while deemphasizing, or at least not prioritizing, those that appear not to facilitate pacific behavior.”

Baum and his co-author Phillip B.K. Potter found two key institutional features influencing democracies’ conflict behavior – strong political opposition, which the authors call “whistle blowers,” and a mass media widely accessible to the population.

“Leaders, both democratic and autocratic, have clear incentives to hide their foreign policy actions when they fail or conflict with the public’s preferences,” write the authors. “Minimizing their capacity to do so requires heterogeneous and autonomous political elites with both independent access to foreign policy information and the incentive to reliably alert the public when leaders stray too far from their preferred policies.”