but these are problems that can be solved--the means are there.
I took "decline" as mentioned in the video to mean an objective and measurable loss in wealth and resources. The wealth and resources are still there, the problem is they've been co-opted by a relatively small clique for their own aggrandizement.
By contrast: the British Empire declined during the 1920s and thereafter due to the catastrophic losses--human, material, and financial--suffered during World War I. This continued after WWII, with the result that the British Empire no longer exists.
You can see similar collapses for the Russian and French empires of the same period, due to much the same reasons, for instance the tremendous destruction of wars and foreign occupation and looting.
The Roman Empire declined due to loss of provinces to encroaching migrations, and a steep decline in its agriculture.
Nothing comparable is happening to the United States today. Our problems are mostly of our own making, and we can well afford to fix them.
I'm bothered by this talk of "American decline" precisely because it feeds into the MAGA narrative that we need "a strong man" to reverse it. It was used against Biden-Harris, and repeated so often that masses of people believed it despite the actual facts. Crime during the Biden administration was down, as was child poverty--until the GOP repealed SNAP--as was inflation compared to "other developed nations." Objectively speaking the United States is still a behemoth on the world stage. The economy of California alone dwarfs that of most European nations.
The irony is that the very problems you've cited were all caused or exacerbated by Republicans, who then use this "decline" narrative to attack Democrats.
Rather than talk about some general "decline of America" I think it would be much better to focus on the issues you mention one by one, and not feed into the MAGA narrative.