We also have to realize that China is going through a huge period of explosive growth and change and a large number of Chinese people are unhappy. Problems of pollution, mass dislocations, and worse yet for the communist government, rising doubts about its censorship and wisdom. In short, if the USA does nothing, the new China will become more open, and be more Western friendly, while a communist government sows the seeds of its own self destruction.
But just any other nation, nothing will unite the Chinese people more than General issues like Taiwan. Which is why feel its foolish to get into a pissing contest with China over Taiwan. As it is, a general reunification along a Singapore type autonomy model is the bloodless end result, and probably what the Chinese Government wants in the 30 year long term.
And as the Chinese economy expands, their main worry will be an equally expanding India. And to a certain extent, an expanding Russia that again starts tapping Siberian resources China also covets.