OK, more subtle, less apocalyptic:
China's Xi guarantees order in the transition to separate but equal Koreas.
Price is US removal of US troops, except perhaps token observation force.
China achieves the latter day Asian "Sphere of Influence"
I don't see Japan allowing any increased US presence. There isn't much else for forward based forces.
Don't get me wrong, compared to an outright nuclear exchange, its the price we should pay. Its China's sandbox now. The real question will be which bed Japan eventually ends up in.