Well the Korean War is called the forgotten war for a reason.I simply don't follow that. It seems to me that dismantling the Japanese empire actually had a stabilising effect on the region.
The communists victory in China was one of the greatest blunders in modern times. Even if the Japanese had to lose their holdings in mainland China or Manchuria, keeping Imperial Japanese forces under the command of CKS would still have prevented the communist takeover. So then maybe let Japan keep Formosa in exchange. All hypothitical. But I really don't see it stabalizing.