The Chinese government is thinking that the good times it is experiencing will continue forever. They won't. China is simply moving up the technology curve, following the exact same path every other country did before it when they industrialised.
Once China reaches parity with the other modern industrial nations, it's economic growth will fall back and from then on it will grow no faster than anyone else. A new world equilibrium will come to pass.
This phenomenon has happened before with the UK vis a vis the rest of the world. For a while in the nineteenth century the world economic system was that most of the manufacturing took place in the UK, the rest of the world supplying markets and materials. Once Germany, France, the US and elsewhere really industrialised the dominance of the UK soon faded, even as the UK continued with the same rate of economic growth (actually UK growth rates were higher in the 20th century than the 19th).
The Chinese Yuan will become a major currency, of that there is no doubt, and it will diminish the current high level of dominance of the dollar. The USA is far too large and far too wealthy to be eclipsed though. The dollar has not rendered the Yen, the Pound, the Deutshmark, the Swiss Franc or many other currencies obsolete, or noticeably impeded any country's ability to run up debt.
The US government and people are going to have to get used to a world which is not so dominated by them and set up for their convenience. The Chinese though are also going to have to learn how to operate on a world scale without offending everyone by being patronising and arrogant, or just buying up everything they desire without regard for the consequences. Like we in the UK have had to do (much as we hated having to do so).
