The vision of a nuclear-weapon-free world is as old as nuclear weapons themselves. One way or another, the idea of complete nuclear disarmament has always been a part of the international political debate, which, of course, includes the United States. Only recently, however, has this idea entered the U.S. political discourse in a way that it is safe for "mainstream" U.S. presidential candidates such as Barack Obama to openly call for nuclear abolition--if only as a distant goal. This is partially a result of a call for a nuclear-weapon-free world in a January 2007 Wall Street Journal op-ed published by four former high-ranking U.S. officials (Henry Kissinger, George Shultz, Sam Nunn, and William Perry). Their call has already been endorsed by a number of their former colleagues, and we should expect new interesting, high-profile endorsements in the near future.
Some of my colleagues who have been advocating nuclear abolition for a long time argue that the motives of these U.S. politicians are self-serving and even imperialistic. The United States, they say, has finally figured out that a world where other countries have nuclear weapons is getting increasingly difficult to manage. I don't think this is the true motivation of those who signed the op-ed or have since endorsed its vision; indeed, nuclear weapons are obsolete, and the realization of this fact is simply finding its way into mainstream politics.
But getting support for the idea of a nuclear-weapon-free world from U.S. political leaders might be the easiest part of the effort. Regardless of whether U.S. politicians are motivated by idealism or cold calculation, the rest of the world will certainly look at their statements with suspicion. Take, for example, Russia, a country crucial to any serious attempt to move nuclear disarmament forward.
Largely due to the economic recovery of the last few years, Russia has busily modernized its strategic forces and invested a lot of effort and resources into upgrading the support infrastructure for these forces. It's building new land-based and sea-based ballistic missiles, strategic submarines, and early warning radars and satellites. In itself, this modernization is not entirely incompatible with the idea of disarmament--one can even argue that it might be easier for Russian leadership to agree to dramatic cuts in its nuclear forces now that it's demonstrated that it can sustain strategic parity with Washington. The real problem in Russia is that the idea of nuclear disarmament is completely absent from the public and professional discussion. Even President Vladimir Putin's opponents are more likely to criticize him for not doing enough to enhance strategic forces rather than question the growing reliance on nuclear weapons.
In this environment, a U.S. call for complete nuclear disarmament will certainly revive old worries about U.S. military capabilities that have existed in Russia for a long time. One of them is that U.S. conventional forces, with their high-precision weapons, could be used in a preemptive attack to destroy most of Russia's strategic launchers. Another is that U.S. missile defense could further help neutralize whatever retaliatory potential Moscow might have left. Neither of these claims would withstand serious scrutiny, but unfortunately, this doesn't matter much; there are enough people in Russia who will make these arguments, and Russian politicians will be happy to pretend to take them seriously.
In reality, from a national security viewpoint, Russia, similar to the United States or any other country, would be much better off without nuclear weapons. Nuclear weapons may have played a role in the past, but they cannot possibly deal with the kind of security threats countries face today. But it will take time for Russia to start a serious (or any, for that matter) discussion of whether it really needs nuclear weapons. Having U.S. politicians endorse the vision of a nuclear-weapon-free world helps enormously, but it's only a start. Eventually, Washington will need to deal with Russia's perceptions of U.S. policies and do a better job of dispelling the notion that the U.S. security posture (whether backed by nuclear or conventional weapons) threatens Moscow, a deeply held belief among the Russian public.