I read recently that a lot of top scientists, especially physicists, in the USA came there as a result of WWII (either fleeing Germany beforehand, or leaving Europe during or after), people including Einstein, Bohr and Pauli (and pretty much all the immigrant physicists worked on the Manhattan project). These scientists drew other scientists, students, etc and fed the scientific community in the USA. Now, many of the world war II scientists are dead, and although obviously good scientists have resulted in the form of their students and others they drew in, their influence is waning and the flow on effect is diluting and the USA is losing the scientific advantage they had as much of it was externally generated.
The list of top people who came to the USA fleeing Europe is astounding, and when you look at the name, you can see that science in the USA could easily have coasted along on that wave very easily with little input or encouragement from the government. Now that the wave is subsiding, science really needs to be a serious focus in the USA.
Interesting question though - although I know the USA got a lot of external input in physics particularly, and is regarded as lagging behind now in this area, does anyone know if the USA has a home-grown lead in any area of science?
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