There is a risk that someone will use, by accident or design, one or more of the 17,000 nuclear weapons in the world today, rendering useless the standing mutually assured destruction principal of nuclear deterrence theory. Simply, the threat of nuclear weapons did not end with the Cold War—these weapons, possessed by states large and small, stable and unstable, remain an ongoing nightmare and painfully uncomfortable reality. Joe Cirincione is president of Ploughshares Fund, a global security foundation, and the author of “Bomb Scare: The History and Future of Nuclear Weapons” and “Deadly Arsenals: Nuclear, Biological, and Chemical Threats.” He serves on the Secretary of State’s International Security Advisory Board and is a member of the Council on Foreign Relations. He is a former member of President Obama’s nuclear policy team and now operates at the center of debates on nuclear terrorism, new nuclear nations and the risks of existing arsenals. In Vail, Joe Cirincione will discuss the best thinking and worst fears of experts specializing in nuclear warfare and assess the efforts to reduce or eliminate these nuclear dangers. This includes outcomes and realities of the Iran deal and the likely threat of terrorist access to and implementation of nuclear bombs. He will also discuss the differences and risks of varying dirty bombs and their risk.