I'd be curious just how much of this "America as Modern Rome" analogy is becoming common wisdom, and realizing that Johnson is using the analogy in a different (and much more apprehensive way) than many other contemporary (albeit mostly American - nothing like patting one's own back after all, and what better way to pat one's own back than by analogizing one's own country to the most powerful and long-lived republic and empire in the history of mankind...)
Many of us will be forgiven for stifling a bit of a laugh. America's "Republic" is barely 200 years old, it has rarely been anything but a tool for facilitating further accumulation of wealth (excluding a brief period from the 1930's to the 1970's) and foreign adventurism (no period to exclude here) so it is somewhat amusing to see these paeans to what America once was as opposed to what those evil people are trying to get it to become.
Let's not lose sight of the fact, for instance, that George Dubya Bush's vision of America is one from the past - the pre-Roosevelt era America (and by Roosevelt I mean Teddy, not Franklin) that was so good to his class, and less so to most other classes. The America, in short, which has obtained for most of her history. "Domestic tyranny" was indeed the order of the day, with the Army regularly brought out to break strikes and kill recalcitrant workers, help steal land (and not just from the autochtones) and engage in imperial adventures abroad as well.
So it is somewhat disingenuous to compare Rome, a proper Republic for 500 years or so before descending into the Empire which eventually would rot, to America, whose Republican credentials have most always been at best spotty.
But if Johnson is set on comparison to the classical period, he could do worse than to cite the Seleucids -at root the product of colonization (and therefore more earnest, if less succesful, colonizers), turned back on its home hellenic base, chronic over-reliance on hard power rather than soft, and hopelessly over-extended. And as a result, far less long-lived than Rome. (And, icing on cake, America finds itself bogged down in precisely the same parts of the world today...)
Don't know if the Seleucids (or the Romans, for that matter) believed their own bullshit as effectively as the Americans though. It is quite possible America comes out, historically, with the highest marks on that score. Silk, sow's ear and all that. Nil aon leigheas ar an ngra ach posadh
The only bad thing about the Rome series is that the feelings are too modern to connect with the public....that's the only problem..for example,, people go around in Rome minding their own business which is flagrantly against everything we know about the public space in Rome.
A pleasure I therefore claim to show, not how men think in myths, but how myths operate in men's minds without their being aware of the fact. Levi-Strauss, Claude