When the Cold War ended more than two decades ago, the shadow of nuclear catastrophe lifted on both sides of the Iron Curtain. This year, that era of relative comfort could well draw to a close; alternatively, the West’s efforts to prevent that from happening could trigger a crisis of such gravity that countless millions will be affected. If that sounds like an alarmist prognosis, consider the situation in Iran. Despite an ever-tightening net of economic sanctions – not to mention a covert campaign of sabotage – Iran is drawing inexorably closer to achieving the ability to build nuclear weapons....