Why would USA fight China? It is our biggest trading partner.
China is on the road to freedom, a road upon which there is no turning back. The biggest mistake that China made was accepting Hong Kong back into China. Now the Hong Kongers are spreading the gospel of democracy throughout China. It is only a matter of time until China passes a new Constitution with individual rights similar to ours.
Democracies very seldom fight each other. (I did not say "never".) The solution for World Peace is the democratization of all nations.