Why do some interstate rivalries end while others persist? Why do some states decide to pursue peaceful relations while others remain stuck in militarized competition? Using evidence from five nuclear rivalries along with quantitative evidence from the universe of interstate rivalries since World War II, Christopher Clary, MTA/ISP Pre-Doctoral Research Fellow, will demonstrate that domestic economic conditions motivate leaders to pursue conciliatory policies toward historic rivals when those leaders have firm control over their state's foreign policy institutions.