China's growth has been impressive, and it is a fantastically dynamic country, but it still has significant disadvantages. The portion of its population that is still in poverty exceeds the entire population of the United States, and its government is ramping up its repression of dissent, which is a troubling sign. The transition to a consumer economy will not be easy, and there is still the danger of uprisings. I'm old enough to remember talk of the Soviet Union destroying the American Empire, a united Europe destroying the American Empire, OPEC taking over the world, Japan rising and surpassing America, and now of a Chinese Century. Somehow the US is still on top. The US has so many inherent advantages, and the rest of the world so many inherent disadvantages, I don't see a loss of American dominance until at least 2050. China will require a significant social reorganization before it can surpass the US, and it looks like the pressures on infrastructure caused by climate change will probably derail that possibility.