Almost all discussions about the United States and the future of nuclear weapons policy refer to two now- famous editorials in the Wall Street Journal, in which the four statesmen - George Shultz, William Perry, Sam Nunn, and Henry Kissinger - lay out their vision for a nuclear-free world.1 The latest Adelplii paper, entitled Abolishing nuclear even proposes a concrete plan for achieving this vision, an effort ambitiously undertaken by George Perkovich and James A. Acton.2 For a moment, one cannot help but feel a tingle of optimism as attitudes seem to be changing, even at the elite level.Offering a sobering contrast to the preceding vision are the words of Robert Gates, who remains secretary of defense under Barack Obama's presidency. Delivering a speech at the Carnegie Endowment for International Peace in October 2008, before the elections and the announcement of his appointment, Gates addressed the challenges of nuclear weapons in the 21st century.3 His vision is profoundly realist, calling for the development of the reliable replacement warhead and arguing that the United States cannot ensure the reliance of its deterrent without undergoing strategic modernization or nuclear testing in the near future.Is America's nuclear future so black and white? President Obama will have to face these dilemmas while confronting the ongoing nuclear modernization of other nuclear states like Russia and China and dealing with the nuclear ambitions of a couple of rogue states. We have a unique opportunity to assess Obama's commitments on several nuclear issues, as expressed during his campaign and in the months prior to his inauguration, leaving others free to speculate as to their feasibility. In this article, we start by briefly outlining President George W Bush's legacy in terms of nuclear weapons policy, a legacy that is heavily focused on counterproliferation initiatives. Then we outline Barack Obama's nuclear agenda as introduced during the presidential campaign. Finally, we assess the implications of these positions for American allies, and in particular Canada.Our main argument is that a move toward more traditional arms control is on the ascendancy and had been identified by both candidates as desirable. Indeed, this has the potential of providing a framework for the many initiatives undertaken during the Bush administration to address nuclear proliferation and nuclear terrorism.4 But more importantly, and more urgently, the focus is shifting toward the strategic arms reduction treaty (START), which is set to expire in December 2009.THE NUCLEAR LEGACY OF GEORGE W. BUSHNot unlike his predecessors, the most recent Republican president emphasized American nuclear superiority to uphold deterrence. However, with the introduction of the nuclear posture review in 2002, there was a conscious attempt to move beyond deterrence in an effort to address the top security threats of the post- September nth world - terrorists, rogue leaders, and their ability to develop weapons of mass destruction, including nuclear terrorism.5 Also significant in the review was the introduction of the triad, whose stated aim was the diversification of both nuclear and nonnuclear options to offer a more flexible response to threats. The triad comprises a strike leg that includes both nuclear and conventional forces, missile defences, and a responsive infrastructure to adapt its forces to the security environment.6 Accordingly, the nuclear posture review calls for a new emphasis on developing nuclear bunker busters and surgical warheads that could reduce collateral damage. Conventional precision weapons, on the other hand, could be assigned to targets that have in the past been reserved for nuclear weapons. Some have argued that such a tailored doctrine combining nuclear and conventional capabilities will not only blur the distinction between the two types of weapons but increases the likelihood of nuclear reaction and escalation. …