I guess I am the Tyrone Slothrop of Northwestern University.  I’ve been doing research on the theory of the “democratic peace” – the finding that democracies rarely attack each other.  This has been called “an empirical law” in international relations.  This idea is famous enough that it is offered as a rationalization for spreading democracy by both left- and right-wing politicians.

Why might democracies be more peaceful?  And how about a regime like Iran?  Fareed Zakaria says : “Iran isn’t a dictatorship. It is certainly not a democracy.”  It is something in the middle.  There are elections but an elite also controls many things such as the appointment of the Supreme Leader who has enormous power.

I have done some research with David Lucca and Tomas Sjostrom where we offer a theory for why these regimes which we call limited democracies might be the most warlike of all.  And the data does suggest that countries like Iran are very warlike, especially when facing a similar limited democracy.

Here is brief attempt to explain the theory informally – it is done using game theory in the paper.  Conflict occurs via combination of greed and fear – two of the causes of war according to the great Greek historian Thucydides.  Each side does not know if the other is motivated by greed or fear.  Greedy leaders are hawkish.  But, even if one side is not greedy, they turn aggressive because the other side may be greedy.  So, both sides become aggressive whether it is because of greed or fear of greed.  We study how political institutions can control greed or stimulate fear.

In fact, the logic above is our model of dictatorship where leaders interact with no thought for the wishes of their citizens.  It is our pure model of greed and fear.  It is inspired by the famous logic of the “reciprocal fear of surprise attack” due to Thomas Schelling.

In a democracy, the voters may punish a leader who starts a war unnecessarily. As leaders want to stay in power, this controls greed.  But the voters may also punish a leader who is weak in the face of aggression.  This unleashes fear as democratic leaders are aggressive in case they are too dovish in an aggressive environment. So, democracies can be peaceful against each other as dovish voters control their leaders.  But they can turn aggressive very rapidly if they are concerned their opponent will be aggressive.  In a dictatorship, the leader does not fear losing power but no-one controls his greed.

Now, suppose the leader can survive in power if he pleases the voters or if he satisfies a hawkish minority who favor war.  This regime has some properties of  a democracy – the leader survives in power in the same scenarios as the leader of a full democracy.  But he also survives if he starts an unnecessary war – just like a dictator would.  The leader only loses power if he is dovish in the face of aggression.  Then, neither the average citizen nor the hawks support him.  This type of regime which we call a limited democracy is the most aggressive of all.  The leader fears losing power and the voters cannot control his greed.  So, a little democracy can make things worse if it leads to a regime like this.

The theory leads to a bunch of predictions which we try to confirm in data.  I took a shot at explaining the ideas in a talk I gave to Kellogg MBAs.  The video is here in case you’re interested (you need Real Player to view it).  The article is here (you need Adobe Acrobat to view it).