Writing at The Cipher Brief China hawk Gordon Chang questions the prevailing wisdom that China’s influence over North Korea is actually quite limited:
Beijing may not have the power to change Kim Jong-un’s mind—it’s possible no one can do so—but the Chinese could convince regime elements that it was no longer in their interests to stick with either their weapons programs or Kim himself, who, by the way, is not especially popular, after his unprecedented demotions, purges, and executions.
This would be a particularly consequential time for Beijing to act because the North Korean regime looks especially unstable.
I think the situation is actually darker than the one Mr. Chang portrays. I think that the only reasonable conclusion is that, not only does China think that the collapse of the Kim regime would not be in their interests but the North Korea nuclear weapons program is actually in its interest. All of the materiel that the North Koreans have imported to pursue their program has either come through China or with China’s tacit permission.
So China is trying to simultaneously minimize their own risks and maximize their gains. I think their calculation is wrong and that they’ve released an uncontrollable tiger but we’ll know more about that in due course.
China requires that any state on the Yalu be a Chinese ally, and they will go to war to prevent a US-friendly regime on their border. As to North Korea’s weapons programs, they do tie down significant American and Japanese resources and deflect attention from China itself. Note how the artificial island controversy has subsided while everyone is focused on North Korea’s missile tests.
A preemptive strike on North Korea is off the table because South Korea and Japan will not agree to it. They would be the main victim of the ensuing war, a war which would involve both China and Russia, as the last Korean War did.