Iran—the same country that took American diplomats hostage twenty-five years ago and whose leaders often refer to the United States as the “Great Satan”—may be on the verge of developing nuclear weapons. How worried should we be? What can the United States do, if anything, to defuse the threat of a nuclear-armed Iran? Is a military response feasible? Or should the United States focus on strengthening the movement for democratic reform within Iran? Peter Robinson speaks with Larry Diamond and Abbas Milani.