Yeah, but the Chinese and US economy are tied to each other through that mechanism. It would not be good for China if the US falls.

The resources thing is really the only reason, why one country could benefit from the others gloom. But e.g. for building up a long term energy solution, cooperation would help everybody much more than confrontation. Here is the point, that even in the best possible scenario a confrontation could only give some more years of cheap oil consumption for the winner. A common enemy helps to bring different people together and this common enemy is time/energy shortage.
Peak oil is as much a chance as it is a risk.

Der Amerikaner ist die Orchidee unter den Menschen
Volker Pispers