The small glimpse of Panmunjom shows that tensions on the Korean Peninsula can be eased. Perhaps the US aims to maintain controllable tension to justify and strengthen its military presence in the region.

The US and the DPRK have been locked in a stalemate for some time: Pyongyang wants a peace treaty first and Washington demands that Pyongyang first abandon its nuclear weapons program. The DPRK uses the US' refusal to sign a peace treaty to conduct nuclear tests, which, however, doesn't threaten the US because of Pyongyang's failure to develop missiles with nuclear warheads powerful enough to strike the US mainland. The US, in turn, uses the DPRK's actions to beef up its missile defense system in Asia on the pretext of protecting its allies against Pyongyang.

The DPRK's nuclear tests, however, pose a problem for China and the ROK. The DPRK conducted its third nuclear test a little more than 100 km from China's border. Therefore, like Seoul, Beijing too is strongly opposed to Pyongyang conducting any more nuclear tests. China, in fact, supported the sanctions that were subsequently imposed on the DPRK.

But by refusing to promise that it will not take any military action against the DPRK, the US has provoked it to build nuclear weapons and tried to drive a wedge between Beijing and Pyongyang. The US is playing the DPRK nuclear card also to create a rift between China and the ROK and keep the latter deeply entrenched in Washington's camp, which could prove damaging for Beijing and Seoul both, because China is the ROK's largest trade partner and the ROK is China's third largest trade partner country.

Some believe that China doesn't support Korean reunification, because once the Peninsula is united the US could redeploy its 30,000 troops on China's northeast border using the Washington-Seoul military alliance as pretext. This will undoubtedly pose a big threat to China's security, especially because it is widely believed that the "pivot to Asia" policy of the US is targeted at China.

China is indeed worried about security on its northeast border. But an unstable Korean Peninsula poses a far greater risk to China. China supports Korean reunification because peace, rather than tension, on the Peninsula best serves its interests.

After almost seven decades of division, the two parts of the Peninsula have developed huge gaps in terms of political systems, economies and people's well-being. Efforts to narrow the gaps, rather than China's policy, are vital for rapprochement between the two sides on the Peninsula. But it is equally important that the US abandon its Cold War mentality and stop using the Peninsula as its chessboard to plan its strategic moves and create trouble in the region. China is not the key to Korean reunification, the US is.

The author is an editor with China Daily. zhuping@chinadaily.com.cn