I mean… that depends on what metric you are going by, I suppose.
Not by personal happiness, or by health outcomes, or “freedom”, or safety, or education, or (non-military) technology, or … well the list gets rather extensive.
To be fair, the USA did used to lead the world, e.g. being first if not to space then to the moon, and we sequenced the human genome, and computers were invented here, and there’s Hollywood serving up movies and culture all over the world, etc., so I am not knocking any of the past achievements. Notably, after WWII we did get a bit of an “uneven” start compared to countries like the UK that were bombed by Germany whereas the USA emerged fairly unscathed, and yet we took that headstart and really went for it! We indeed were the most successful country in the world - unquestioned by almost anyone.
However, lately… well, “the economy” is still booming, but most average people are going to die significantly sooner than their parents generation did, possibly by a terrorist event such as a school shooting that we have nothing whatsoever to try to stop, health outcomes are abysmal, and many millennials and especially Gen-Zers strongly doubt that they will ever be able to afford a home, seeing how homes have become “investments” rather than places to live in, colleges costs have quintupled, most jobs today for younger people are “temporary” positions in the gig economy, etc. etc. etc.
You do bring up a good point: compared to the rest of the world we still do have it pretty good, in some ways. It is just that compared to how we ourselves used to have it e.g. 50 years ago, we are doing significantly worse, relatively speaking.
Look at almost any list, e.g. the top 10 scientific discoveries, or engineering accomplishments, and America barely makes those lists anymore. Other nations with drive & heart like India or China are sacrificing so that they can outpace us. That’s fine I guess, they needed their turn:-). But at some point we should ourselves: what exactly makes us “successful”… these days?
You might think that I am one of those that hates America, but I do not think of myself that way, it is just that I am questioning our place and how it has changed over the years. Though perhaps I am simply paying attention to the wrong sources, so if you want to send me something to read or watch that answers that, I would like to learn. So far though, everything that I have learned lately ends up just depressing me b/c it at least appears to be a decay, and not just morally.
Is this the new “Honey Badger Don’t Care” meme?