On your first point, it is certainly the case that many scientists came from abroad, and in fact that is still the case today, you don't need Nazi persecutions for that. But we are talking about whether the academic system produces game changing research, not where the researchers were born (in fact if anything,the fact that people are attracted by this model is a testimony to its effectiveness).

As for the 90%, agree, that's where I found that number. But do the exercise of listing all the major technological advances you can think of that mattered on the XX century, and I think you will likely end up close to that.

What exactly constitutes a 'major technological advance'? If we're counting Turing Awards by university affiliation, then I believe 90% is probably a good estimate for the US share (https://en.wikipedia.org/wiki/List_of_Turing_Award_laureates...). If we're counting Nobel Prizes in Physics, Chemistry and Medicine, it suddenly becomes less clear why this should be true (https://en.wikipedia.org/wiki/List_of_Nobel_laureates_by_uni...), and if we're counting the number of Fields Medals (the most relevant award given the subject of the post), the numbers seem to suggest that the US contribution to pure mathematics is not as dominant as you might imagine: https://en.wikipedia.org/wiki/List_of_Fields_Medal_winners_b...

In any event, I think this is all getting rather silly. I was simply making the point that historically science in the US has benefited tremendously from having a large number of capable people that were trained within a different system. Where they were born is absolutely irrelevant. A certain W. von Braun was indeed an American, as were his 'major technological advances' that many in the US are rightly proud of, but he was very much a product of German science (I hope you don't find this point controversial).

In Physics the 2 giant contributions from the XX century (Quantum Mechanics and General Relativity) were developed in Europe.

In Mathematics the big highlights of the XX century: the Hilbert Program, the Bourbaki group, computability,the FLT solution were mainly made outside the US.

First satellite? First man in space? USSR

Europe was a big contributor to the first computers: Colossus, Zuse's Z2.

The Germans were pioneers in rocketry and ballistics as it is sadly very well known by the rest of the work.

In Biology: Watson, Crick, Monod,Ian Wilmut,Maynar-Smith made fantastic and foundational contributions

Medicine? Antibiotics,discovery of tetanus vaccine, immunological agents, vitamins, all made outside of the US.

That's not to say that American has not make fantastic contributions, The Apollo program, the invention of the transistor, the invention of the Internet are highlights of American ingenuity and glorious gifts to the rest of the world.

But pretending that all good science is made only in the US and the rest of the world in some sort of scientific backwater is just a sad indictment of the American educational system that formed you.

I upvoted for the finesse of your last line.