The study analyzes the major developments in nuclear arms control and disarmament in the first two years of the Obama presidency, focusing on the impact of the new disarmament agenda on the nuclear nonproliferation regime. The essays compiled here probe the Obama administration's at times conflicting emphases on nuclear arms control and disarmament, and their implications for deterrence and the determination to confront proliferators such as North Korea and Iran. Also explored here are international treaties for control and disarmament of other weapons of mass destruction; the tension in US-Russia relations over the American missile defense program; and implications of the new agenda for the Middle East, particularly as it relates to Israel and the nuclear realm.