China already is behaving aggressively, expanding territory under its control (e.g., in the S. China Sea) and threatening to do so elsewhere (e.g, in the Senkaku islands). They may try to justify their next aggression by blaming someone, but that isn't meaningful.
The same applies to Russia, which already had annexed part of Georgia and clearly had designs on the southern Ukrainian province of Crimea (which did nothing to protect them against missiles). They justify their behavior, like all bad actors throughout history. Look at the Nazi's list of excuses as they snatched territory in the run-up to WWII.
The U.S. and others can't be intimidated into inaction while aggressors like Russia and China keep moving forward, for fear of 'upsetting' their tender feelings.
Not trying to make up excuses for any of the parties involved here. Just pointing out that China likely won't sit on its ass as this happens.
The only silver lining I see is that maybe this will provide China with the incentive to just throw Kim under the bus (literally under a bus... or a tank) and put some less belligerent puppet in his place.