To answer point by point:

- yes the Civil War could have literally been our Berlin Wall. And maybe we needed that. But the actions of the post war, for better or worse, did unite us enough to not have that happen.

- The gilded age should have also been the fall of the US. It arguably is the setup to the stock crash. But decades of collective opposition lead to a leader who could guide us out of thar crash with some of the most progressive policy we've seen.

The crimes of the 70's was manufactured a lot in part of the US government. And whole Vietnam was bad, the common American was never in danger over these issues past yet another recession. It wasn't quite the endgame we've seen other times.

Meanwhile, now: you can argue that this empire was falling for 45 years. With a few ups, but overall trending down. If the bronze age can fall in 100 years, I see no reason the hyper accelerated digital age can't fall in 30-40.

We can still be saved by yet another huge progressive push, but will we this time? It'll depend so much on the next 2 years.