personnel. Once home, the returnees would contribute to industries that compete with US based industries or take jobs that are offshored from US multinationals, shifting the locus of scientific and technologic leadership overseas while the United States struggled to replenish its S&E workforce by developing domestic talent. We are nowhere near that extreme, but it may be useful to keep it in mind as a worst-case scenario.
In a favorable scenario, highly skilled international graduate students and postdoctoral scholars enter S&E positions. Those who stay in the United States become permanent residents and citizens; those who eventually return home enter valuable collaborations with US colleagues and become informal ambassadors who communicate the democratic values of scientific research and of the United States. They order US products for their businesses and provide expertise for local divisions of US industries. At the same time, the United States might use graduate-student fellowships, higher postdoctoral pay, and other incentives to increase the flow of the best US talent into S&E. We are not at this extreme either, but it may be useful to keep it in mind as a best case to work toward.