I realize the title of this question is a bit odd and apparently counter-intuitive, and might give someone a good chuckle, but bear with me for a second.
The People's Republic of China and the Democratic People's Republic of Korea (DPRK, also known as North Korea) are long-time allies, and spent the latter part of the 20th century united by being communist countries outside the Soviet bloc (with China seeking to become a "third power").
Importantly, DPRK has also acted and maintains its role as a buffer state between China and the US-aligned South Korea.
However, it is my understanding that:
- The chances of a conflict involving North Korea under the current regime and the US are growing monotonically
- China probably does have no incentive in entering a costly war with the United States, at the very least not in this decade.
- Even if China keeps neutral, it would probably not want to have a philoamerican government installed in North Korea, for obvious reasons.
- Even if China keeps neutral, I believe it would deem undesirable to have American troops that close to home for the duration of a conflict.
- China has so far been unable to defuse tension in the area through ordinary diplomatic action.
It seems to me that, simply because the other alternatives are worse, China would have good reason to urgently install a new regime or government in DPRK, through:
- diplomatic action
- espionage, or even...
- full-on military action
In fact, I would be inclined to think the optimum from a Chinese point of view would be staging or supporting a coup to remove the current leader along with high ranking officials while still keeping the WPK in charge, while, of course, denying all involvement.
What are the disincentives for China in doing that, and what are the superior alternatives?