actually after 2nd world war US wanted China to grow strong and became a strong ally in the Far East to counter USSR. they wanted China to occupy part of Japan, but KMT only want Taiwan back. US even hope China under KMT can be like US with the Democratic political system. it will be like 2 strong countries allied in 2 different continents. but too bad, during that time the people and leadership of China were not ready for such thing. sigh!
after VJ day, the Chinese Nationalists rested all hopes in the United States to aid China for the country rehabilitation. Chiang Kai Shek could have made a deal with Stalin. if it happened, the Kuomintang would have no more problems with the Chinese Communists. the Kuomintang chose to stick with the United States. it was a mistake. the United States betrayed and badly let down Chiang and the Kuomintang. the US chose to watch from the sidelines and abandoned China to its tragic fate in 1949. the American aid to China from 1945-1949 was totally exaggerated.
"our China policy was our worst diplomatic failure in the Far East. i believe that we will pay dearly for it for the next 100 years" - General MacArthur. 1951.
"all the events that have happened since the close of the war show that American policy, foreign policy, directed toward China was to push the Nationalist Government over the cliff and not make it look like we had done it?"
- US Senator Hickenlooper to Secretary of State Dean Acheson who denied the accusation.