File photo shows Seoungju residents chant slogans during a protest against the government's decision on deploying a US THAAD anti-missile defense unit in Seongju, in Seoul, South Korea, July 21, 2016. The banner reads "Desperately oppose deploying THAAD". [Photo/Agencies]

Is it one of the thorniest diplomatic challenges for China? Undeniably it is when the Democratic People’s Republic of Korea conducted its fifth nuclear test on Friday morning.

No wonder the voices may flare up again that China should play a vital role in reining in the DPRK. However, all parties concerned should remind themselves it’s high time they stopped a war of words, and truly shoulder their responsibilities to stop the vicious cicle of security dilemmas on the Korean Peninsula.

The fifth nuclear test by the DPRK will intensify tensions on the Korean Peninsula, push the nation itself into greater international isolation, pave the way for more possible sanctions, undermine its goal to develop the economy, and further endanger China’s border security. By developing nuclear weapons, the DPRK will never achieve security, but instead face more tit-for-tat countermeasures from the US and its allies.

It would be wrong?for the DPRK to miscalculate that China would connive its nuclear program at the cost of China’s own security. China vehemently opposed the United States’ plan to deploy the Terminal High Altitude Area Defense System?on the Republic of Korea, which will enhance the US surveillance over China’s missiles in Northeast and East China. But THAAD will not weaken China’s stance on the denuclearization of the Korean Peninsula, as THAAD and the DPRK’s nuclear program both pose acute security challenges for China.

The US may regard itself the only winner on the dangerous chessboard of the Korean Peninsula. The DPRK’s nuclear capabilities can hardly pose true threats to the US homeland, but enable the US to grip the ROK under its alliance when the ROK and Japan keep aloof because of historical rows.

Uncle Sam also brings a conundrum for China. The THAAD system more or less cools down the warmest-ever China-ROK ties since the establishment of diplomatic ties in 1992, while the DPRK’s nuclear program thwarted the efforts to maintain a robust traditional friendship between China and the DRPK.

The US also misguides the international community to put pressure on China to keep the DPRK in check. US President Barack Obama pushed China to “tighten up” sanctions on the DPRK during a sideline meeting at the just-concluded G20 summit, while US presidential front runner Donald Trump vowed to take a harsh stance on the DPRK and blamed China for the DPRK’s provocations.

But will the US truly win if the game of nuclear tests vs. THAAD intensfies? The US is playing with fire by casting a shadow of insecurity on East Asia and may engulf its interests in the region once the situation gets out of control. An unstable Northeast Asia will disturb regional development, not only China, but also in Japan and the ROK, which will eventually hurt US national interests.

No one can keep intact in the dangerous lose-lose game. It’s high time for the US and the ROK to halt the plan to deploy the THAAD in the ROK, and the DPRK to abandon its nuclear ambition.