People have been predicting the end of America's hegemony for decades. A lot of times the "signs" that America's fall is upon us are really similar. People seem to say this with some sort of anticipatory glee, as if to think that they're unique to make that kind of a call. The United States has a lot going for it that it competition doesn't have and although it's really fashionable to call Americans in general fat, stupid, arrogant, boorish, and lazy, this seems to ignore two very important things: That other countries face some very serious problems of their own that keep them from lapping us as civilizations and that we as Americans are more than willing to point out our own flaws and work on them.
The second is a very powerful thing and just might be the key to America's lasting power. I wouldn't root against us. This country is obviously far from perfect, but when it's at its best, my GAWD it's a great place to be.