The idea that "culture" explains the American reliance on imported talent is as lazy and wrong as the idea that some kind of "innate American IQ deficit" is to blame.
The simplest (and therefore most plausible) explanation is statistical. Given that the US is (by far) the most attractive country for people wanting to do cutting edge science or engineering, the pool of talent they can draw on is worldwide.
Over 96% of humans are not born in the USA; Therefore one would anticipate that most of the best engineers and scientists in the USA will be born elsewhere, just as a consequence of arithmetic.
It's just the 'Brain Drain'.
If you have the talent to get to the very top of the engineering world, then you probably can't fulfil your potential in Kenya, or Brazil, or Pakistan. China or India might have a use for your abilities, or you might go to an EU country, or even go to Australia or Canada, but the bulk of the facilities and money for the most advanced R&D is in the US, so America is going to be on your list (probably top of your list). India and China between them host about a quarter of humanity, but they don't host anywhere close to a quarter of the top R&D roles worldwide.
Before WWI, Europe was the place to be. The best and brightest Americans (and indeed the best people from across the world) moved to the UK, Germany (for chemistry), or France (for aviation), to pursue opportunities created by their scientific and engineering talent.
Now the USA is the place to be. Top engineers and scientists tend to clump together where the money and facilities are. National boundaries are an impediment, but a wise government*, finding themselves to be the number one destination of choice for the world's top talent, will minimise that impediment.
If I were to suggest that the English have a culture of preferring intelectual pursuits over the development of skills as a football player; Or that English people are "innately bad at soccer", you would think I was nuts.
But how else can we explain the fact that so many players in the English Premier League were not born in England, (or have parents who were not born in England)?
The idea that the best foreign footballers are invading England because the English are culturally averse to soccer, or are innately bad at the sport, is clearly wrong; These foreigners are coming because the EPL is the most challenging and rewarding place in the world to use their skills. And of course there are more foreigners than there are locals; 57 million is a smaller number than 8 billion.
335 million is
also less than 8 billion. You would know that, if it wasn't for your innate lack of mathematical ability, and your culture of rewarding sporting achievements over mathematical ones.
* Of course, your actual government is trying to maximise that impediment; Perhaps because they are innately unwise, or have a culture that denigrates wisdom.
