The popular uprisings of the Arab Spring have left a leadership void that Islamist parties have been quick to fill. A longtime supporter of former strongmen like Egypt’s Mubarak and Tunisia’s Ben Ali, the U.S. now faces the uncomfortable result of Arab democracy—the rise of Islamist parties that are less amenable to the West than their autocratic predecessors. Will the Islamists, who once embraced violence, slowly liberalize as they face the difficulties of state leadership? Or will it mean the growth of anti-Americanism and radicalization in the region?