You need only look at the makeup of every MBA, MEng, MS, and STEM PhD program. 50% European and 50% Asian, all foreigners (i.e. immigrated on a student visa). I

You need only look at the makeup of every MBA, MEng, MS, and STEM PhD program. 50% European and 50% Asian, all foreigners (i.e. immigrated on a student visa). If there was no brain drain then you'd expect mostly US permanent residents/citizens.