Any actual war China wages against the US will be in cutting off manufacturing for critical components in countries like Taiwan, Singapore, Malaysia, etc. where microchips/electronics manufacturing/industrial components are often made. When we can't get castings and other components to keep factories, automobiles, infrastructure going because of parts scarcity, we'll be in a bad spot. Those things can be solved given a long enough timeline, but you can't erect forging plants, ore mining, and manufacturing all overnight. Even doing it in the span of a decade takes serious effort.