Over an ominous photo of North Korean strongman Kim Jong Il, a recent issue of The Economist asks, “Who can stop him now?”

I have a simple answer to that question: China, if it musters the gumption.

In my dealings with senior Chinese leaders, I have found them wise, practical, enamored of constructive change, intent on preserving their gains and keen to shape global developments to serve their interests.

So I wonder why they drag their heels in dealing forcefully with North Korea, in my opinion the undisputed No. 1 pariah of the 21st century. China’s verbal admonitions and embrace of gentle sanctions in response to Pyongyang’s testing of nuclear weapons contradict every characteristic mentioned above.

China has shown infinite patience with North Korea, all the while urging it to step into modern times, reform its economy and foreswear nuclear-weapons testing – to no avail. Waiting for North Korea to come around will almost certainly result in disappointment. As fervent practitioners of brinkmanship and desirous of clinging to the global spotlight they now command, the North Koreans have no incentive to act decently.

It is time for China to terminate its famous “lips-and-teeth” relationship with its nominally ideological brother. Indeed, the moment is right for Beijing to contemplate a regime change in North Korea.

A few years ago, as Kim was returning from a visit to China, his private train encountered a devastating explosion near the two countries’ border. Various explanations emerged, none of them too convincing. I wondered at the time if the catastrophe suggested evidence of a bungled plot to assassinate the North Korean despot. I further speculated whether such a scheme might have had its origins in China.

I recall certain reader responses concluding that the idea was absurd, but others begged to differ. Indeed, they thought it was entirely plausible that the Chinese might have been indicating their growing discontent, as well as their ability to reach out and neutralize Kim at any time of their choosing.

It is not surprising that similar ideas have entered the discussion about Chinese-North Korean relations in 2006. Persistent intransigence on Pyongyang’s part, especially regarding the question of nuclear-weapons testing, threatens China’s progress.

At best, such provocation creates uncertainty. At worst, it portends regional instability and possible conflict, along with a refugee crisis (North Koreans streaming across the border), which would delay or disrupt China’s desire to perpetuate its economic miracle. Beijing has managed to post an impressive average of 9.5 percent annual growth for the past quarter-century. The countries that will enable it to continue moving in that direction are its main trading partners – the United States, South Korea, Japan and Taiwan, among others – not North Korea.

China has more than the mere satisfaction of ranking among the world’s top economies at risk here. Its government and Communist Party derive much of their legitimacy from their ability to expand economic opportunities and bring more and more Chinese into the realm of the “haves” each year. One false move by North Korea, and some of China’s worst nightmares could spring to life.

A potential part of the solution lies in a much more aggressive round of diplomatic arm-twisting that I know China does not savor. At the same time, Beijing has not even come close to using its influence over Pyongyang.

Failing that, I would leave it to the creativity of strategists in China to come up with a way to nudge Kim from power. As The Economist notes, China certainly could, if it wished, “starve North Korea’s people and turn off its lights.”

Would such a step by China produce anger, panic and possibly the very regional conflict that most people seek to avoid? Or would it inspire a coup that could usher in a more reasonable government, perhaps even one that would pursue the reform path that everyone but Kim and his cronies see as the future?

If the Chinese are as wise, practical, enamored of constructive change, intent on preserving their gains and keen to shape global developments to serve their interests as I believe, they will intervene and stop Kim’s insanity.