It enables the US to weaken other countries by draining away their intellectual capacity. Think of it as 'Cognitive Imperialism' and then it fits in well with the historical patterns of how the US treats the world.
> It enables the US to weaken other countries by draining away their intellectual capacity
Are you implying that if they don't emigrate they'll be properly utilized in a way that is a threat to the US's current hegemony? If so, why aren't these countries doing that now?