So in other words is the reason the US got pushed out in the first place.
Once again, I don't think you actually know much about history, or at least this particular conflict. A lot went on behind the scenes, Il Sung was petitioning Moscow and Beijing for aid the day coalition forces crossed the 38th parallel. This involved many meetings and deliberation, Stalin only agreed to help after Mao straight disobeyed orders and attacked. Mao only attacked because coalition forces were making ridiculous progress into NK. If we had stopped at Pyongyang I doubt anything more would have happened. Either way the USA knew what they were doing, and did it anyways. So if fear of Chinese retaliation was the reason we never invaded again, why did we risk it in the first place? Perhaps because a sovereign nation was being attacked by a super power and its two local puppets? If we were truly warmongers we wouldn't have cared about China, and would have invaded again, because we want to, according to you.
China was also not very powerful under Mao. That's why. China has become increasingly powerful since then and likewise equally more fearsome. So much so, that American doomsday fantasies always involve China destroying the US or at least coming close.
...yes? Do you know anything about geopolitics?
Uh no. Do Britain and the US every have their ships pass and have their fighters fly around each other in a display of force? No. China and the US are not allies and are antagonists of one another. You don't know shit about geopolitics, apparently. You hear of these events happening with Iran, China, and Russia. All three of which are at odds with the US.
Less than 2 minutes of research and I can find China advocating for sanctions of Kim Jong Il in 2006. Thats not even Jong Un, its Jong Il...
So about 10 years out of a 70 year relationship...
I mean... the United States is pretty good at finding any reason to invade a country, we've most certainly come up with drastically different explanations in the past. It's also very unlikely that we would have any claim to their mineral resources in the event of a war, as South Korea's main objective in that conflict is reunification.
No, our companies would "buy" the rights to the minerals from a puppet government like they always do.