Saying that one country like China will NEVER surpass another country is a statement of idiocy, especially considering how for much of recorded history the Chinese were actually scientifically and technologically well ahead of the rest of the world.
If history has taught us anything, its the fact that no country can stay at the top in anything forever.
Could unwashed Gauls and Germans achieve scientific supremacy over the Romans? Yes, and they did.
Could backward Europeans achieve scientific supremacy over the Arabs, Persians, Indians, and eventually Chinese starting in the 1600s? Yes, and they did.
Could the United States, one of the countries hell-bent on acquiring scientifically-superior German scientists after WW2 achieve such supremacy over others? Yes, and they did.
Could the Chinese eventually achieve scientific supremacy sometime in the future with its rapidly changing economy, education, civil and political reforms, etc... ??? Yes, and they are rapidly doing so (http://www.youtube.com/watch?v=ws5y8A_zUsc)
China has the fastest growing economy, and with a larger economy comes advances in liberal applications such as science. With more funds they will be able to make more progress, it is really that simple. As long as their economy continues to grow at record pace, it is not unreasonable to presume their science goals will increase.
China has a much greater population than the US, and its standard of living keeps increasing. Meanwhile, the US standard of living keeps sliding, as does the US educational system. Unless the US does something serious-- and it doesn't seem like that's going to happen any time soon, considering basic science like evolution isn't even being taught properly-- China will come out on top.
There is no way that China will achieve science supremacy. The United States has prided itself on constantly being the front-runner in science and math, and a large portion of that is due to the strength of the US brought upon by our diversity. No other country can tap into that kind of a resource like the US can, and even if China DID increase and become more of a threat, it is the US's competitive nature to rise to the occassion.
I do not believe China will ever achieve science supremacy. China does keep increasing but they do not seem to have the imagination and creativity that other countries do, which is a key to science. Also other countries are developing schools to focus on science which will allow them to keep up with China.