Because relocating across oceans is hard and only the high IQ manage the journey.
It's the same reason the only Mexicans you find in Europe are brain surgeons and rocket scientists.
However I do agree that all you need to succeed in the States is a not-too-far-below average IQ and a culture that's not completely retarded, which unfortunatly excludes certain demographics.
Because relocating across oceans is hard and only the high IQ manage the journey.
It's the same reason the only Mexicans you find in Europe are brain surgeons and rocket scientists.
However I do agree that all you need to succeed in the States is a not-too-far-below average IQ and a culture that's not completely retarded, which unfortunatly excludes certain demographics.