Moon is into ...rapprochement...(Sunshine 2.0 I think it's called - but I could have that way wrong.) He's also not at all keen on THAAD. He's actually said he's prepared to visit Pyongyang on the issues. This will meet with China's favour - and to be fair, you can see his point. 45's bellicose stance makes it highly likely that Moon will soon have no country and no people to speak of.
It puts 45, internationally, in a bit of a pickle though. He can't go into NK like a conquering warlord without SK backing.
Much will depend on Russia's views.
(Sorry that that was so short.)