Anyone that believes the US just magically wins most athletic competitions because we are just somehow magically better because we are American is kidding themselves.
It is my belief that US athletes leverage the US technological edge by taking cutting edge drugs that haven't been banned yet while simultaneously cracking down on their foreign competition using drugs our athletes were using not long ago but that are now banned.
Two words - Lance Armstrong
Yep. There is a constant cat and mouse game going on between the chemists who manufacture, tweak and modify the PEDS, the chemists who advise those who write the rules and the chemists who create the drug tests.