[chii]

A possible explanation that the US is still somehow leading despite the drop in proficiency in education (if that is indeed actually true), is that the high level of tech and investment done in the 70's and 80's are still playing out (and returning dividends). It might take one or two generations to pass before the cracks show up as real problems - like a demographic transition, you cannot patch it after the problem is discovered, but must anticipate and pre-empt the problem.

If the education in the US is in decline, then the next 2-3 decades will show a decline in innovation and tech improvements coming out of the US.