the goal is simple make all the money that the united states owes to china be owed to the united states by china
The US sends several billion dollars to the Republic of China to defeat Mao and the Communists. When the Communists are defeated, the US continues to provide aid, to force the Soviets into increasing their own military spending to defend two fronts more heavily then OTL.
After the Soviets are defeated, the US begins to demand repayment of all the loans they gave, with interest.
You'd need to make Truman and Chiang hate each other a bit less.