What the hell you are getting so bent out of shape for?

 

500 - 800 MIRV ICBMs are just the synopsis of the worst case scenario. Even if the US starts to design and invest in a new Intermediate-range Nuclear capable missile, it takes time for it to produce and deploy it. That would give China the time necessary to formulate an appropriate response. 

 

Further there is the problem of where to deploy these missiles. I doubt any nation would partake in the deployment of such nuclear missile. South Korea is definitely out. They are trying to convince North Korea to denuclearize. How would the deployment of such missiles be perceived by the North Koreans and on their efforts to denuclearize? Not even Japan would be stupid enough to deploy these missiles. If they do, Japan would become a legitimate target for Chinese Intermediate nuclear missiles. There is a difference between having a nuclear umbrella and having nuclear missiles strapped to your back.

 

So after all is said, US withdrawal from INF Treaty may have little or no effect on China...the very least, not in the immediate term.