The States and China were friends to combat

Japs in WWII, although they also confronted in the Korean peninsular in 50s, and the Vietnam semiisland in late 60s to early 70s. As a result of these events, both USA and China are familiar with one another and know both strength and weakness. Today, these two great nations have more commonalities than differences in terms of interests - that both favor a stable and peaceful world than a chaotic one. Therefore, there is any excuse for the States and China to fight each other in long run to destroy this planet.