As for China, the SARS incident has shown up the tremendous weaknesses in how it is governed. Making money there is rather like trying to pan for gold in the Klondike - it's risky, corrupt, and wild. Unless China moves to a more enlightened system of government, there is no chance they will be able to compete with America's stable laws and trading systems.
Regards, Ivan
Actually the situations are similar. While it's not a bad here, the increases in both the EU and US are due to immigration, legal and illegal, and the birthrates of the immigrants, particularly the illegal ones.
That said, I think we've got enough people. At some point lots of people stops being an asset and starts being a liability. China and India are past that point and we are near it somewhere, IMHO. Quality counts more than quantity. Ask a Baathist.
Nor our biggest actual advantage, (comparitavely) free markets and the right to property.