In recent years, "a nuclear weapon-free world" has become a worldwide campaign. US President Barack Obama pledged to take steps for a nuclear weapon-free world in his speech in Prague on April 5, after the US and Russia issued a joint statement on April 1 declaring that the two countries will continue to negotiate a new nuclear weapons reduction treaty.

In 2007 and 2008, former US secretaries of State Henry Kissinger and George Shultz, former Defense Secretary William Perry and former Senator Sam Nunn, jointly wrote articles in the Wall Street Journal calling for a nuclear weapon-free world. Australia and Japan established the International Committee on Nuclear Non-Proliferation and Disarmament last September; UN Secretary-General Ban Ki-moon called for nuclear disarmament several times in his speeches; and, people from all walks of life proposed Global Zero in December.

It is the immediate as well as long-term need to make nuclear disarmament return to the diplomatic agenda of the US and Russia. During the eight years of the Bush Administration, bilateral disarmament of the US and Russia almost came to a standstill. The First Stage of Strategic Arms Reduction Treaty (START), which was signed by the US and Russia in 1991, is due to expire on Dec 5, 2009, and the Nuclear Non-Proliferation Treaty (NPT) Review Conference will be held again in 2010. The US and Russia should not only implement their disarmament commitments to the non-nuclear-weapon states but also consider how to continue reducing their nuclear arsenals after the expiry of the treaty.

Nuclear weapons played a role in maintaining the "balance of terror" during the Cold War. To some extent, nuclear deterrence even reduced the likelihood of wars. However, considering current international security environment, there is an off chance for nuclear wars to occur between powerful nations. The gigantic nuclear arsenals of the US and Russia tend to be a heavy economic burden and are potential safety hazards.

Moreover, challenges posed by the non-proliferation mechanisms also require the US and Russia take actions on nuclear disarmament. The risk of proliferation of nuclear weapons has risen after DPRK's nuclear tests. More and more countries are considering development of civil nuclear projects for coping with global warming and energy shortage. This, in turn, will increase the risk of proliferation of nuclear technology and materials. The existence of an underground nuclear smuggling network implies that it is also possible for terrorists to resort to "nuclear terrorism".

In the prevailing situation of nuclear proliferation, which is not an optimistic scenario, if nuclear powers such as the US and Russia continue to maintain huge nuclear arsenals and emphasize more on nuclear weapons in their national security strategies, they will lose the moral high ground to prevent other countries from developing nuclear weapons.

A nuclear weapon-free world should not be merely a beautiful dream. All countries, especially the US and Russia, should jointly make it come true by taking necessary action. In order to substantially reduce the huge nuclear arsenals of the US and Russia, the two countries should negotiate a new treaty aimed at achieving irreversible nuclear disarmament. The US and Russia should also reduce the role of nuclear weapons in their national security strategy. They should regard nuclear weapons as defensive means of the last resort. Meanwhile, countries without nuclear weapons deserve their safety to be guaranteed. This would require the nuclear powers, especially the US and Russia, to provide assurances that they will not use or threaten to use nuclear weapons against them.

Missile defense is an inescapable problem in the future nuclear disarmament process. After the US withdrew from the Treaty on the Limitation of Anti-Ballistic Missile Systems (ABM Treaty), theoretically there's no limitation on the development of the missile defense capability of the US. It will significantly influence the nuclear disarmament policies and positions of relevant countries. At present, the missile defense forces of the US cannot threaten Russia, which has a massive nuclear arsenal. If the US is still averse to engaging on the missile defense issue, the process of nuclear disarmament will not go too far. When former US President Ronald Reagan and former Soviet Union leader Mikhail Gorbachev met in Reykjavk more than 20 years ago, the two countries almost reached a consensus on eliminating nuclear weapons, but it eventually failed because of the Star Wars plan.

After all, "a nuclear weapon-free world" is desirable. Although the ideal cannot be realized in the short term, the appeal of such a global order will possibly restart the nuclear disarmament process and rebuild confidence in the non-proliferation of nuclear weapons.

The author, Fan Jishe, is associate researcher at Institute of American Studies, the Chinese Academy of Social Sciences.

(China Daily May 7, 2009)