There's even a big book on my shelf "The Senate Intelligence Committee Report on Torture" which catalogues extensive examples where US intelligence tortured people or was instrumental in their torture, insisted this had unlocked important information and then eventually walked that back as investigators started to dig in.

The US still more or less remembers how to improve and that book is an example of how such improvement could start, what changed in the last decades is that more and more Americans don't want to. The word "Again" is crucial, MAGA don't want to make America great, they want the America from their nostalgia. It's hollow, that's not what they wanted but it could never have been otherwise.