from Polybius to Toynbee seem to have missed, the rise of a grabber class that seizes the bulk of the wealth and power of everything from wealth7 city states to vast empires and causes them to decline and thebn crash into oblivion.
The grabber class runs the gamut from a cabal of merchants to an organized military toa tight group of inter related merchants to authoritarians who are usually just the public face of these groups and can be ousted or assassinated at any time on their whims.
The US did a lot of things right at its inception: separation of powers, checks and balances, civilian control of any military, and all based on a democratically elected representative system which has become more small "s" democratic as time has gone on. What they failed to do iscome up with a mechanism to prevent the rise of a grabber class via corporations, something Madison himself recognized but which he could find no traction to prevent.
Rich men want two things above all: to get richer and to live forever, their own class so far above the rest of us that they can live out their lives without seeing any of us or having to consider us, at all, except as a repository of spare parts that will help them live forever*. They pose an existential threat not only to states and political systems, but to anyone and everyone outside their class. Their near universal fascination with eugenics and keeping bloodlines intact will wipe them out, but it takes a long time. Any new iteration of the US experiment has got to address and find a way to prevent their rise because even after this bunch fades, other will try to take their places.
*This ranges from instances of partial cann;balism in the archaeological record (a great hunter's spar throwing arm, a courageous fighter's heart, etc) to bones used in Asian medicine to the current crop thinking transplanted organs will allow them to live forever, thus displaying their ignorance of both the aging process and the limits of transplant medicine. Yes, they will die.
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