The big difference...tourists visit the ruins of these ancient civilizations. Will there be ruins of our current civilization worthy of visitation by future civilizations? Will the “visitors” be aliens from another planet wondering just what the heck was a Hooters...or a Tesla dealership? Upon translating and reading history books of our time, will they wonder why we didn’t defend ourselves when our nations were invaded by other countries? Will future tourists or “alien visitors” learn a lesson from our destruction?
Probably for at least another hundred years there will still be much of the same infrastructure here, and monuments, like the white house, capitol, etc, and the US will still be operating under the same name, but it’s already a good way toward transforming into something beside what it was meant to be.
The Romans had a Senate, which on it’s surface was what we think of as a representative democracy, but it didn’t have what we call checks-and-balances, and also the Senators came only from the upper classes, and they were usually sponsored by powerful people and groups. Oh wait, that sounds rather familiar. Doesn’t it?
Well, our power elites have the ability to stuff the judiciary with like minded activists, so most of our “checks and balances” don’t really create much balance. The scales tip.
The interesting thing about all that was how the Senators promoted and protected the class system at the expense of the masses, it appears at first glance in history that the emperors and ceasars were tyrants who destroyed ‘democracy’ but at least the first few (Julius and August Ceasar for example) were populists who gave a lot more to the masses than the senate ever did. So it’s all a lot more complex than it appears.
The difference is that we have several power (elites) classes, including the huge bureaucracy. In some ways, it’s a stabilizing force, somewhat resistant to political pendulum swings, but in other ways, it crystalizes the power and wealth disparities in our system.
We wont have a coup, by the elites anyway. That’s why we have a silent coup, or a slow transition away from the constitutional protections of the people. The symbols and illusions of constitutional institutions will all remain in place, but they will not function to protect the rights of the people as intended.