"WE" won. Who´s "WE"? Athletes who have the US passport, right. Not you, not your family, and probably none of your friends. The US has the largest delegation, and considering this, the performance was rather bad, compared to other nations (especially the Chinese). And who´s the best? I hope you agree with me that it´s the individual athlete who won - and those were mostly NOT Americans, even if the US team got most gold medals (but not many more than the Chinese).
You speak of "quality of man". This is old, some Germans tried it before and called it Aryan. Sorry pal, but the idea of a better race is out-dated... there is no better race, there´s just the better individual.