There is little question that the threat of nuclear war dropped precipitously at the end of the Cold War. It seemed that the days of duck-and-cover drills for school children, rapidly expanding U.S. and Soviet arsenals, and the threat of mutually assured destruction hovering over daily life were over. But then India and Pakistan tested nuclear weapons in 1998. And North Korea tested its first nuclear weapon in 2006. And Iran was caught trying to develop nuclear weapons. And then Vladimir Putin threatened to use nuclear weapons repeatedly when he invaded Ukraine in 2022.
Nuclear weapons today remain a very real existential threat to the future of humanity. Global nuclear stockpiles still have the power to make the planet uninhabitable. International reduction efforts have stalled in part because those with weapons do not want to give them up and many nations, like North Korea and potentially Iran, see them as an existential insurance policy.
Today, the threat of global climate change—playing out in real time—may have more resonance for a young generation of policymakers and activists focused on the survival of humanity than the seemingly dated question of nuclear arms. Nevertheless, the existence and destructive capabilities of nuclear arsenals remain not only a fact of life but also an extremely important consideration in security decisions for countries around the world, whether or not such considerations are always made explicit. This has been highlighted in response to the escalating war in Ukraine, with President Putin threatening—both explicitly and implicitly—a nuclear response to Western intervention (including Boris Johnson's recent admission that Putin casually noted his ability to destroy London within minutes in the early days of the invasion). Along with rising tensions between the United States and China, this issue is, sadly, as relevant as ever.
The continued existence of nuclear weapons as a global security issue compels us to consider the ethics of their continued maintenance, potential use, and position as an instrument of deterrence and political power. One of the pioneering efforts at proposing an ethical framework for thinking about nuclear weapons is Joseph Nye's 1986 book Nuclear Ethics, published in the latter days of the Cold War. In it, Nye walks a path between the proponents of mutually assured destruction and nuclear abolitionists, outlining what he argues is a more realistic and moral path, including ten operational criteria for avoiding nuclear war.
In this spirit, the editors of Ethics & International Affairs are pleased to publish a symposium organized by Scott Sagan in which Nye has been asked to revisit Nuclear Ethics. In the lead essay, Nye reflects upon what has changed since the Cold War and what remains the same. His overall assessment, while providing a few updates to his schema, is that the basic facts of deterrence still hold, all these decades later. Responding, Sagan argues that while there is much truth in Nye's position, he overlooks a few major changes in the global political landscape that heighten the risks of nuclear weapons but also create more possibilities for safer and more just nuclear deterrence policies. Sharon Weiner argues in her response that the concept of deterrence, upon which much of Nye's argument rests, is overly optimistic about the degree of rationality and intentionality that goes into its practice. Any fruitful exploration of nuclear ethics must come to terms with the degree to which luck plays, and has played, a key role in deterrence. Last, Joan Rohlfing argues that just nuclear deterrence is a myth, and that in today's complex and risky world, we owe it to future generations to propose a new strategy for nuclear weapons wherein a breakdown of the system does not threaten to end or fundamentally alter humanity as we know it.
Our hope is that these essays will help to inspire and refocus a discussion on the urgent question of how to create an ethical and just future in a world with nuclear weapons.
