For eight decades, the world has navigated the risk of nuclear war. But what will be required to so in the future? And because that risk is not static, how do we measure, conceptualize, and respond to changes—like when Russia rattles its nuclear saber? What challenges do so-called tactical nuclear weapons pose to deterrence models based on much larger, strategic weapons? And what dynamics influence both the creation and erosion of international arms control frameworks that aim to regulate these weapons? This episode tackles those questions and more. It features a discussion with W. J. “Bill” Hennigan, the lead writer for a new series published by the New York Times called “At the Brink.”