That's what I'm thinking when I watch old PR films about the space program and the atomic energy program that were made back in the 1950s and early 1960s.
There's lots of them on YouTube. You can get a glimpse of a nation that was on top of its game.
I don’t know if there is a technical term for it but it can be said as we advance in knowledge we as a species lose knowledge as well. We would not be able to easily build the pyramids again - we can build a sky scrapper of a tower using steel beams but can’t really do the stone masonry on the pyramid scale well any longer.
Flint tools are inferior to metal in some ways but they are also superior in others - they hold their edge forever and don’t decay like metal does. As we learned to work with metal we lost the ability to flint nap, etc.
I read an article a few years ago that the knowledge to maintain or rebuild some missiles is lost because the people who made them and maintained them retired and died and did not impart that knowledge to a new generation so making a space manned vehicle would mean having to re-learn things known in the 60s and 70s.
Yep.. and a nation that was sure of itself, its identity and its role in the world... that is most assuredly a lost civilization.