A few weeks ago I began writing about some of the foreign policy choices and strategic challenges the next American President will face. One of the most profound issues is whether nuclear weapons still have a role in the 21st Century.

Two decades after the end of the Cold War, the United States and Russia are still armed for Armageddon, with hair-trigger arsenals that could end life on earth as we know it. Does this potential for overkill still make sense? Should Senators Obama and McCain be asking whether it is time not only to start seriously downsizing the world's nuclear arsenals but to think about abolishing them altogether?

Perhaps surprisingly, both candidates seem to agree. Senator Obama says that “America seeks a world in which there are no nuclear weapons.” And Senator McCain gave a recent speech that commits him to the same goal. Indeed, this is an issue that cuts across party lines.

A quarter century ago, President Ronald Reagan declared, "our dream is to see the day when nuclear weapons will be banished from the face of the Earth." And as the former Democrat presidential candidate Senator John Kerry recently pointed out, no less than 17 of the 24 former secretaries of state and defense and national security advisors support moving towards this goal. Western think tanks are already studying the political and technical means by which such an ambitious goal could be reached. Nuclear disarmament is no longer just a banner carried by ban-the-bomb marchers. It's an idea whose time may have come.

And yet ... the public knows almost nothing about this debate and most politicians seem to care little. That's not surprising because the mainstream media pay so little attention to strategic issues.

Most people do not realize that the United States and most of the world's major powers accepted not only the long-term goal of nuclear disarmament but also eventual complete disarmament in the 1968 Nuclear Non-Proliferation Treaty. It was part of a deal in which the nuclear powers persuaded the non-nuclear powers not to seek nuclear weapons themselves.

For the most part, the deal has worked. A few countries gave up their nuclear weapons programs. Some got away with building secret nuclear arsenals – either with America's tacit assent (Israel, Pakistan) or without it (India, North Korea). But the world has not had to face the global spread of nuclear weapons that President John F. Kennedy warned of. "Stop and think for a moment," he said, "what it would mean to have nuclear weapons in so many hands, in the hands of countries large and small, stable and unstable, responsible and irresponsible, scattered throughout the world."

It's the other part of the deal that has not worked. The nuclear powers have gotten rid of some of the warheads they no longer need (the United States) or can afford (Russia), but they have made no serious moves toward abolishing all of them. Indeed, they have been working to modernize their bombs and in 1999 the U.S. Senate simply refused to ratify the international treaty banning the testing of nuclear weapons. In the eyes of the rest of the world, the American attitude has been “do as I say, not do as I do.”

Opponents of nuclear disarmament point out that the threat of nuclear destruction prevented war between the West and the Soviet Union, and that no one has dared use a nuclear weapon since World War II. But there is no guarantee that will never happen. The only sure way of preventing a nuclear holocaust is complete and verifiable nuclear disarmament.

It would take years of careful study and research to devise the means of ridding the world of nuclear weapons. There must be timetables and verification arrangements, but above all it would take new international political and military arrangements to insure that war between major powers is taken off the table as effectively as it was when nuclear weapons were the major deterrent.

Above all, it would take leadership by the United States to create a new world security system, and a firm commitment by a new American president to lead the way. This is not pie-in-the-sky stuff. It's the future of our children and grandchildren.

As former Secretary of State Jim Baker – a wise and hard-nosed realist – recently said, “Nuclear disarmament will take decades to achieve. We should begin now.”