The Democratic People's Republic of Korea said on Friday, its 68th National Day, that it "successfully" tested a nuclear warhead in the morning. This is the fifth nuclear test conducted by Pyongyang since 2006 and the second this year. The DPRK only on Wednesday rejected a UN Security Council statement condemning its latest missile tests and threatened to take "further significant measures".

China's Ministry of Foreign Affairs has issued a statement censuring Friday's nuclear test and urging the DPRK to meet its denuclearization commitments.

In the Republic of Korea, the presidential office reportedly held a National Security Council meeting on Friday afternoon after "a seismic event" of magnitude 5.3 was detected near the DPRK's northeastern nuclear test site.

The nuclear test carried out by the DPRK on Friday should not come as a big surprise given the planned deployment of the US' Terminal High Altitude Area Defense system in the ROK. In other words, the almost confirmed deployment of THAAD, an anti-missile defense system, has prompted Pyongyang to continue its ill-designed foreign policy.

Judging by its latest nuclear test, the DPRK still stands firm on its strategic misreading, believing that by developing nuclear weapons it will pressure the United States to respond to its concerns. That also explains why the DPRK has conducted missile tests this year even though THAAD might not necessarily pose a major threat to it.

Besides, a nuclear test on the 68th National Day of the DPRK also has a noteworthy political implication - that top leader Kim Jong-un will keep expanding the country's nuclear arsenal.

But it does not suggest the situation on the Korean Peninsula is out of control, because Pyongyang's nuclear efforts usually follow US and ROK military moves.

China is determined to divert this trajectory toward a peaceful direction. But admittedly, China's strategic choices in the face of a rising nuclear threat in the neighborhood are limited because of the geopolitical complexity and the denuclearization process may take five to 10 years to complete. So Beijing has been urging all parties concerned to make more concerted efforts to becalm the ensuing turbulence.

Washington and Seoul, in particular, should sincerely rethink their decision to install THAAD on the peninsula and review their other strategic mistakes that have prompted Pyongyang to make the wrong steps.

A vicious cycle is in the making between the US and the ROK on one side and the DPRK on the other, which can make peaceful reunification of the peninsula even more unlikely. In fact, if tensions continue to rise on the peninsula, the DPRK and the ROK will eventually be the worst victims.

The peninsula policies adopted by the US and the ROK are not conducive to lasting peace, as they have exhausted the very few opportunities to replace the 1953 armistice with a peace treaty.

As US President Barack Obama will leave office in four months and his ROK counterpart Park Geun-hye faces a presidential election next year, there is hope their successors (if there is one in the ROK) would make a difference and forge a permanent peace and security mechanism with China.

The author is a researcher in Asia-Pacific strategy at the Chinese Academy of Social Sciences. The article is an excerpt from his interview with China Daily's Cui Shoufeng.

(China Daily 09/10/2016 page5)