For this is no time for nuclear security concerns to be held hostage by dissensions between the great powers, all of whom know how potentially vulnerable they are. A nuclear deterrent can only function in a dispute between established powers who know how much they potentially have to lose. But not even the world's leading powers are immune from the threat of terrorism, whose most obvious exponent is the so-called "Islamic State" and its contacts and supporters in Russia, China, Europe and the USA.

Recent murderous attacks in Brussels, and last year in Paris, have given rise to concern that militants could eventually target nuclear plants, steal sensitive material, and develop radioactive "dirty bombs." China has joined the U.S. in persuading many countries to reduce and safeguard stockpiles of dangerous materials. But there are still large quantities of plutonium and enriched uranium which remain vulnerable to theft and abuse. These are not - or should not be - issues of dissent between the great powers. We are all equally at risk.

It is not only the risk of non-state terrorism which is concerning participants at the summit. A key issue remains the hoped-for denuclearization of the Korean Peninsula. China agrees in principle that it would be better if the DPRK refrained from conducting further missile tests, and has discussed potential U.N. sanctions against its neighbor. Prior to President Xi's meeting with President Obama, the latter held talks with Japan and the Republic of Korea on the peninsular denuclearization issue. Obviously an agreement on this topic will require active Chinese participation.

There are still some tricky issues, beyond the need for safeguards on active nuclear plants. Xu Dazhe, chairman of the China Atomic Energy Authority, emphasized that China remained committed to pursuing the reprocessing of nuclear waste, which is of course a necessary consequence of maintaining civil and military nuclear programs, but nonetheless poses a proliferation risk. China is currently negotiating with France, another major nuclear player, to build a commercial plant to separate plutonium from spent reactor fuel. But this remains a long-term project.

The great hope from the Washington summit is that a strengthened international nuclear safety agreement can be reached, ratified and implemented. In 2005 a partial agreement was reached on amendments to the Convention on the Physical Protection of Nuclear Material, but this has not yet been ratified, due to insufficient support. The U.S. asserts that enough countries are now willing to ratify and that the revised agreement will shortly come into force. If this comes about, the positive and constructive approach taken by China will have played an important, indeed an essential part. It is inevitable that the world's great powers will differ on important global issues, and in such cases tough negotiation will be necessary. But this should not affect issues on which a clear common interest exists.

The writer is a columnist with China.org.cn. For more information please visit:

http://www.ccgp-fushun.com/opinion/timcollard.htm

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