U.S. nuclear weapons were born nearly 65 years ago with the purpose of winning a worldwide war against Nazi Germany and imperial Japan. They grew up to deter a massive Soviet army that threatened to invade and dominate all of Europe. With the disappearance of that threat almost 20 years ago, nuclear weapons entered middle age in search of a new mission—a search that continues to this day. Some suggest nuclear weapons are necessary to deter, or even preempt, the proliferation of nuclear weapons and other weapons of mass destruction. Others believe they are needed to destroy deeply buried, hardened targets in hostile states. But the reality is that only one real purpose remains for U.S. nuclear weapons: to prevent the use of nuclear weapons by others.
That reality has yet to sink in. U.S. nuclear policies remain stuck in the Cold War, even as the threats the United States faces have changed dramatically. Today, the gravest threat comes from the possibility of terrorists bent on delivering a devastating blow against the United States acquiring the capacity to do so with nuclear weapons. This threat is compounded by the dangers of nuclear proliferation, as more and more countries hedge against potentially negative developments in their regions by acquiring the wherewithal to build the bomb.Then there is the increasing global demand for nuclear energy, which will spread the infrastructure necessary to produce fissile nuclear materials still wider. The world, in short, is on the verge of entering an age of more nuclear weapons states, more nuclear materials, and more nuclear facilities that are poorly secured—making the job of the terrorists seeking the bomb easier and the odds that a nuclear weapon will be used greater.
The grave nature of these growing threats has motivated a widespread rethinking of the U.S. approach to nuclear weapons.The most dramatic example is the vision of a world free of nuclear weapons articulated by former Secretary of State George Shultz, former Secretary of Defense William Perry, former Secretary of State Henry Kissinger, and former Chair of the Senate Armed Services Committee Sam Nunn in a January 2007 Wall Street Journal op-ed. Their vision has since been endorsed by no less than two-thirds of all living former secretaries of state, former secretaries of defense, and former national security advisers. Both Barack Obama (D-Ill.) and John McCain (R-Ariz.) have expressed support for it as well. Given this remarkable bipartisan consensus, the next president will have an opportunity to make the elimination of all nuclear weapons the organizing principle of U.S. nuclear policy.
Setting a vision of this kind is vitally important, but it is not enough.What is also needed is a strategic logic that explains how the world can get there from here. It involves four major steps, each difficult but feasible. First, Washington must establish as official policy the limited purpose of U.S. nuclear forces: to prevent the use of nuclear weapons by others. Other purposes are no longer realistic or necessary for the United States. Second, given this limited purpose of its nuclear weapons, the United States should reduce its nuclear arsenal to no more than 1,000 total weapons. This would be more than enough to convince anyone that the United States possesses the capacity to respond to any use of nuclear weapons with devastating effect. Third, the United States must work to put in place a comprehensive international nuclear-control regime that goes well beyond the present nonproliferation regime’s accounting and monitoring of nuclear materials. It must include all fissile materials and provide an airtight verification system to enable the world to move from thousands of nuclear weapons to hundreds, to tens, and ultimately to zero.
Finally, Washington must launch a vigorous diplomatic effort to convince the world of the logic of zero—and of the benefits of taking the difficult steps necessary to get there. This effort should start with its closest and most important allies, then include other nonnuclear states who have long called for such an initiative, and ultimately encompass all nuclear states. U.S. leadership of this international effort will be crucial. And a willingness to act boldly to reduce its own reliance on nuclear weapons and drastically cut its own arsenal can give Washington the credibility necessary to succeed.