>I wonder what was different with American culture 60 years ago that enabled such an achievement?
You should read Peter theil's book zero to one then. In the book, he highlights how the culture have changed from taking deterministic risks to placing non-deterministic bets all over the place to minimize risks. This pessimism according to him came due to the numerous bubbles like dot-com bubble, the real estate crisis, and the clean energy bubble that have gone bust due to over optimism.
You should read Peter theil's book zero to one then. In the book, he highlights how the culture have changed from taking deterministic risks to placing non-deterministic bets all over the place to minimize risks. This pessimism according to him came due to the numerous bubbles like dot-com bubble, the real estate crisis, and the clean energy bubble that have gone bust due to over optimism.