So the author agrees that China is enabling this man in his brinkmanship.  It follows then that despite what the author goes on to argue, China has some influence over this manchild.    China can stop propping up NK's economy, stop allowing Chinese banks to circumvent sanctions.  If money makes the world go round and there is none, kim's world stops going around.  While his general population starves he spends money on weapons, maybe if he suddenly has trouble affording food for himself and his army he'll have no choice but to spend what money he has wisely.

In other words, China needs to step up; he last thing we need is one unstable 'leader' mixing it up with another.

BTW, its not too unreasonable to assume that this manchild is thinking one-step ahead of China when he murders his brother; one way to put an end to the madness would be to put the brother in his place but that's no longer an option.