But the logical conclusion of that premise (if we want to be formal) is that what ACTUALLY makes US grad schools great is equivalent to what incentive these stu

But the logical conclusion of that premise (if we want to be formal) is that what ACTUALLY makes US grad schools great is equivalent to what incentive these students have to become US citizens. I would propose highest salaries in the world as that incentive. There is nothing fundamentally superior about American culture or politics to many other countries, so that seems like the most reasonable conclusion to me. Thus, do you really need to worry about retaining talent after you have assessed the true underlying incentive? The simple answer is no. Americans getting paid more than anyone else, game-theoretically, guarantees the smartest people will not only try but absolutely find a way to live and thrive in America. Speaking of incentives, if we know that is the main driver of smart immigration then one can wonder what is the "true" incentive behind published "research" like this. For example, conclusions like this: >U.S. policymakers can ... control whether the United States remains an attractive and welcoming destination for international talent. are simply not true (at least in attracting the truly best and most desirable candidates).