That was 1989, not 1986. Anyway, back to history, the forces at work behind were USSR (supporting CCP/PRC), Japan (wanting a permanent partition of Manchukuo/Manchuria) and USA (openly supportive of ROC but had other agenda at heart, i.e. not to keep a strong China).
Chiang was very intelligent, he read it well. He used whatever US support to go after the commies first, ignoring Japan. However, that made Japan bolder and more ambitious and embarked on a "co-prosperity" mission, i.e. to have both China and Manchukuo under its sphere.
Chiang could have won way before 1945 by concentrating on the commies at the cost of sacrificing many Chinese lives to the Japanese. However, he was betrayed by his own generals taken in with the commie common front against Japanese propaganda, kidnapped and forced to change strategy.
After Japanese surrender in 1945, the commie propaganda machine was at full volume at they saved China from Japan as KMT was weakly semi-selling the country like old Qing Dynasty. Most peasants and commoners believed it and there was no way KMT could win by then.
