Why We FightBased on two decades of research, the five causes of wars and four ways to stop them. It's easy to overlook that most of the time, war doesn't happen. Around the world, there are millions of hostile rivalries, yet only a tiny fraction erupt into violence. With a counterintuitive approach, Blattman reminds us that most rivals loathe one another in peace. That's because war is too costly to fight. Enemies almost always find it better to split the pie