I'd imagine one reason for this is that in the US, there is really no good career path any more for smart scientists. Becoming a tenured professor is orders of

I'd imagine one reason for this is that in the US, there is really no good career path any more for smart scientists. Becoming a tenured professor is orders of magnitude harder than it used to be. Tenure track positions at even universities that arent particularly known as leaders in science and research regularly get thousands of applications If I were a smart Chinese scientist with degrees from top western universities, and I had the option to return to my home country, start a lab, and perhaps be part of a modern day scientific revolution, rather than spend 3 more years in a postdoc position in the us, id do it in a heartbeat