For context, I recall @Skallagrim arguing elsewhere that as America encompasses the West, we should likewise expect it to shed many of the old "Americanisms" as it becomes a "pan-Western" entity, thereby resulting in a "diluting" effect as it takes on its new holdings and enabling it to assume some of the more "European" traditional forms and structures that others have suggested.
Personally, I think it'll work the opposite way, the groundwork for which is being laid as we speak. As I told him, it seems to me the younger generations throughout the fledgling "Americasphere" are getting more and more "Americanized" through various channels. Regular use of Anglophone idioms and slang, Hollywood-made movies and TV everywhere, American multinationals doing business in their countries, and US politics receiving disproportionate news coverage from abroad, all mediums through which the rest of the Western World seems to be undergoing "Americanization at a distance!" already (despite the "Too little, too late!" objections of PM Meloni and other European nationalists).
Give that process another five or sex decades, and I see Europe and much of the Asia-Pacific becoming (for lack of a better term) "discount Americans" who'll be easily absorbed into the Empire based in America Proper. Holdings that retain their "native" culture for considerably longer, then, will probably be in Africa and the Middle East. As I understand it, they haven't felt the effects of Anglo-American pop cultural domination quite as profoundly, which may make them harder to absorb into the fold straight away.
I would not overestimate the capacity for Americanization.
In the history of cultures, the younger ones always get absorbed by the older ones as soon as they become more or less one.
In the end, it was Rome that succumbed to Hellenization and not Greece to Romanization.
Although it remained Rome, the Greek influence was so strong that it was able to overshadow much of Romanism. To finally prevail over Romanism with the moment Rome split in two.
Byzantium was a unified Greek despotism with a Roman name.
To put it briefly, Rome may have taken Greece but it was Greece that conquered Rome.
This will be the case once America takes over Europe, it will be the Americans who will try to fit in with the Europeans, to eventually become more European than the Europeans themselves.
Of course, here we have a big difference, Europe does not have one unified culture that differs in details like the Greek, but many different ones with different traditions, resulting from really different histories.
I would say more that cultures from the same origin will succumb the most. That is, the British will become more American, the Canadians and so on.
Then there will be cultures that America impresses but do not have their own counterparts of what is most American through as they fit in, they will gain American characteristics. (I believe one such will be German).
Cultures, on the other hand, which are further from Americanness and have analogous traditions similar to those of America, will by their very nature repel Americanization. Only on the surface will they have American characteristics, which in reality are their own characteristics. (I'm shooting that Dutch).
The last separate group are cultures that have survived attempts at erasure, these will always be resistant to Americanization, and no matter what amount of soft power is used, it will eventually fizzle out like a duck.
As is well-established by my many previous comments on the matter, I rather think that in
every single case of a universal empire being established, the result was an imperial culture-- which did
not correspond neatly to the pre-existing culture of the incipient nation.
Specifically, while the statement "actually Greece conquered Rome" is stretching it a bit, that case
can be made. Indeed, proponents of "the old Republic" (most especially Cato Maior), in the period leading up to the true decline of that republic, warned against "Hellenism". And they mentioned the Greek influence the most because it was the most prevalent, but essentially it was a sort of "globalism" or "cosmopolitanism" that they opposed. They saw that the old
Romanitas -- the national identity of a distinct Roman ethnic group -- was becoming diluted.
We see this now as well, and indeed "America First!" is an expression of such ideas. There are some users on this site who fly completely off the handle whenever the notion of America becoming a universa empire is brought up. These users (and people like them) vehemtly insist that America is unique, and most remain a republic, and that foreigners can never understand this, and blah blah blah. So on and so forth. If they paid attention to history, they'd know that they represent a doomed strain of though. But they adhere to this way of thinking precisely because they (incorrectly) believe that their favoured nation -- America -- is somehow outside of history. (And in that, they are regrettable akin to modernists, who think that their favoured
period -- "modernity" -- is outside of history.)
The historical truth is that
Romanitas didn't die. It changed. Rome, in conquering, was conquered. In changing others, she was changed herself. Because in overflowing the world, the world flows also into you.
That is truth of the world-empire.
That is why it's never just (over even "mostly") a one-way street.
The main philosophy of Imperial Rome was stoicism; a Greek school. The language favoured by the elite was Greek, not Latin. The religion that ultimately capitvated the Empire was Christianity, originally a Jewish sect. The weapons and gear of the military changed, in ways influenced by the best alternatives and the smartest innovations that all the other peoples within the Empire could contribute.
And in exchange, all these things were... made Roman. And even as Rome embraced these influences, she exerted her own formative influence upon all others. Even as the Roman elite came to correspond in erudite Greek, the masses of a thousand nations learned to speak a version of Latin.
This was the new
Romanitas. Forever changing and bringing change. Without question it was Roman. But the Romans of the old Republic would not have recognised it.
In the same way, in the event of an American universal Empire, that which is understood to be "American" in AD 2400 will not be immediately recognisble as such to the Americans living today. But such is the nature of time. As the Greeks said it: you do not step into the same river twice.
Not like that'll stop "cross-cultural" exchange in which America's holdings bring foreign foods, foreign souvenirs, foreign traditions, and (of course) foreign words into the fold that "Core" Americans happily take to, of course. But from a macro-historical perspective, that's window-dressing, and I'm inclined to think the fundamental "Americanisms" will remain intact, due to the countervailing effects I outlined above.
I think the fact American media, pop culture, and business throughout the Western World is far, far more "24-7-365" than attempts to Romanize the Greeks ever were may shape the nature of the American Empire in ways that preserve more of the old "Americanisms" than the number of old "Romanisms" the Roman Empire inherited. Certainly, it doesn't disprove the overall macro-historical thesis @Skallagrim outlined, but I'd say there'll be significantly more "wiggle-room" than most would think in terms of "High Culture-specific" details — and in my mind, this is one of them.
From historical precedent, and as outlined above, I rather think the trend may be reversed. America may introduce many outward-facing elements across the world (what you call window-dressing, although I'm not that dismissive of it); and at the same time, I rather think that much of the deeper stuff may actually come from Europe instead. There's a reason the Romans adopted Greek philosophy: the Greeks had been thinking about it a bit longer.
After all, if America wants to think about -- say, scholasticism... then they'll
have to turn to the European tradition. All of this was being thought up in Europe before Columbus was even born, you see.
This is not to imply that America is some hollow entity that will exert political power, and then be "filled up" with European culture. Rather, it enforces the notion that the accretion of a Universal world-system (and its culture) is always a process of fusion and synthesis. The expectation that "it'll be different this time!" is a dangerous one, because it's always tempting, and almost always wrong. So a would caution against that.
Jokes aside, this is rather to be expected, although one should always remember that history likes to play on people's expectations.
It's just as well that in the 31 century, the US may already be a memory, torn into small pieces and Canada and more specifically Canada Proper a completely separate country, one of many in America.
Certainly true. Although I'd note that, like China, North America is actually ideally positioned to "fall back together" in a recurring cycle of rebirths. It has oceans on two sides, the Gulf and the Isthmus of Panama on one side, and the Arctic on the last remaing side. Better natural boundaries don't exist! Meanwhile, the Mississippi basin s basically the ur-example of a civilisational heartland. So America itself may well be an "eternal civilisation" that, like China, always falls back together again after ever period of division.