Seventeen years ago, while serving as an Iran desk officer in the U.S. State Department, I asked a more veteran colleague about the latest inflammatory statement by Mahmood Ahmadinejad, then the Iranian president. My colleague responded: “Stop paying attention to Ahmadinejad. Only focus on Iranian Supreme Leader Ali Khamenei. He makes the important decisions.” He added: “But don’t worry. Change is coming. Khamenei”—who was then 69 and widely believed to have cancer—“could die at any moment.”