There's little innovation in (say) India and China because talent is not enough; you need capital and free markets.
Also, as far as I know countries do not "encourage" their citizens to go to US. Individuals choose to go to US on their own. It's not like they're embarking on a government-funded trip.
Also, as far as I know countries do not "encourage" their citizens to go to US. Individuals choose to go to US on their own. It's not like they're embarking on a government-funded trip.