Looking at how other empires have "collapsed" without being invaded or the military dividing up and declaring fiefdoms, it's been a slow decay of less and less effective centralisation (while still having de jure centralisation) as powerful people and organisations in regions increasingly view other regions as separate.
I think the US military is too organisationally coherent for an Alexander the Great kind of situation. While people do get attached to their commanding officers, it's not nearly as close to the heroic classical period, and you get used to new commanding officers pretty quickly assuming they're not complete assholes. We do make jokes about how wonky/privately captured US Military procurement and logistics can be, but this hasn't translated into factionalism per se, just bloat. I am also willing to be proven wrong on this, especially if the funding dries up or the US Military suffers some major losses. I feel like things like Iraq and Afghanistan, the losses there were lower than the defending population and the type of warfare allows the command structure an easy "out" for its self-confidence.
I also don't think the US will get territorially invaded. Naval landings suck at the best of times, and it's surrounded by allies, bases, and intelligence assets. No sane military is going to make that jump. Inasmuch as we valorise guerillas here, they're only good at defence where there is support amongst the local population. Again, open to see this changing, but I don't see it for the foreseeable future.
I also don't see the US Military (as in... The DoD, pentagon, Army, Navy, etc) being divided up territorially. For instance, a portion of the army becomes "The Texas Border Defence Army". There are a lot of political motivations to keep this the case.
Things like the national guard, police, and other "military"-like forces I definitely do see becoming more separated. Not necessarily with the "border crisis", but you can see the outline of it with the Texas National Guard. If cops get brought in from out of state as well, which states do this and which don't will also define these blocks. We're also partly seeing the outline with abortion laws. Whether or not these issues become "states rights" things, or if new issues are brought in (e.g. banning trans affirming care across all states instead) are all issues that you'll see further diversification but also weakening of federalism. If, say, a future Republican fed tries to ban trans affirming care and Washington State decides not to follow through, what happens? If DC stops funding to Washington State (I should have chosen different examples), the idea of federalism is weakened. If the law just isn't followed and local state government doesn't comply with the FBI, what happens? Do doctors in Seattle stop being able to practice elsewhere in the US? Does DC send in the troops to reign in the Washington state?
The world will look very different with Texadollars and Californibucks, I think that's a long way down the road. But separated economies and laws which both still sort of use the US dollar (e.g. Seattle would import a lot of USD through corporations, say) is part of the beginning.
Remember that with the Roman Empire, the Catholic Church and Feudal lords carried on many of the legal structures even after the Roman Empire stopped being able to be said to be a single entity. Systems of debt peonage carried over, the division between "arable land owning military citizen" and "slave/debt peon/non-citizen" carried over to "lord" and "peasant". The Catholic Church maintained Imperial divinity even though it was now a pope instead of an Emperor. Not with the exact same things, but that's what I imagine US Empire will look like in a few hundred years.
This, of course, is alongside the tightening of Capitalist contradictions. Rich get richer even as profits get squeezed (until mono-oligopolies spread around the world), poor get poorer and more numerous and desperate. But the legal and nationalist concept of "The United States of America" I think will look like the above. Also, the US Military and intelligence apparatuses will continue to defend Capital since that's why they exist.
but that's what I imagine US Empire will look like in a few hundred years.
I can never take anyone seriously who talks about any of the current geopolitical entities still existing in "hundreds" of years, let alone the already-in-early-collapse US empire specifically. As others have said, collapse is (more often than not) a process, but that process can happen extremely rapidly if the medium it exists in allows for it or even demands it. That medium is global society and it is a vastly different kind of entity now than it was a century ago, even more different than it was before the industrial revolution, and barely comparable to it was around the time the Roman Empire that often erroneously gets used as a metric of comparison. Sometimes people like to refer to how it took more than a century for it, or some of a number of older empires to fall, but they aren't accounting for how different the material conditions are now, such as the conditions that allow for information to travel instantaneously to opposite ends of the globe (to name one obvious example) and how significantly these differences inevitably increase the rate of societal and political change.
The rates of technological, social, and environmental change are all increasing, and not just as a linear increase, it's exponential. By the turn of the next century the world will be entirely unrecognizable from what it is today. Climate change alone will ensure that, with mass migrations (and die-offs) happening on a scale humanity has never seen. That much is unavoidable. It's insane to think the US will still exist in a few hundred years. The face of the planet even, in terms of the biosphere, will be completely different as a result of the ecological collapse wrought by climate change, and some people here think the current unstable political entities will survive that? It never ceases to surprise me when communists, ostensibly with an understanding of historical materialism, fail to get this.
edit: I don't mean to go off on you in particular, keepcarrot, I generally really like your comments. This is just something that bugs me when I see it come up here, in part because it makes me feel like even my fellow comrades don't understand how dire things are now in a way that they weren't in the past and on a scale that wasn't even registered in the past.
Looking at how other empires have "collapsed" without being invaded or the military dividing up and declaring fiefdoms, it's been a slow decay of less and less effective centralisation (while still having de jure centralisation) as powerful people and organisations in regions increasingly view other regions as separate.
I think the US military is too organisationally coherent for an Alexander the Great kind of situation. While people do get attached to their commanding officers, it's not nearly as close to the heroic classical period, and you get used to new commanding officers pretty quickly assuming they're not complete assholes. We do make jokes about how wonky/privately captured US Military procurement and logistics can be, but this hasn't translated into factionalism per se, just bloat. I am also willing to be proven wrong on this, especially if the funding dries up or the US Military suffers some major losses. I feel like things like Iraq and Afghanistan, the losses there were lower than the defending population and the type of warfare allows the command structure an easy "out" for its self-confidence.
I also don't think the US will get territorially invaded. Naval landings suck at the best of times, and it's surrounded by allies, bases, and intelligence assets. No sane military is going to make that jump. Inasmuch as we valorise guerillas here, they're only good at defence where there is support amongst the local population. Again, open to see this changing, but I don't see it for the foreseeable future.
I also don't see the US Military (as in... The DoD, pentagon, Army, Navy, etc) being divided up territorially. For instance, a portion of the army becomes "The Texas Border Defence Army". There are a lot of political motivations to keep this the case.
Things like the national guard, police, and other "military"-like forces I definitely do see becoming more separated. Not necessarily with the "border crisis", but you can see the outline of it with the Texas National Guard. If cops get brought in from out of state as well, which states do this and which don't will also define these blocks. We're also partly seeing the outline with abortion laws. Whether or not these issues become "states rights" things, or if new issues are brought in (e.g. banning trans affirming care across all states instead) are all issues that you'll see further diversification but also weakening of federalism. If, say, a future Republican fed tries to ban trans affirming care and Washington State decides not to follow through, what happens? If DC stops funding to Washington State (I should have chosen different examples), the idea of federalism is weakened. If the law just isn't followed and local state government doesn't comply with the FBI, what happens? Do doctors in Seattle stop being able to practice elsewhere in the US? Does DC send in the troops to reign in the Washington state?
The world will look very different with Texadollars and Californibucks, I think that's a long way down the road. But separated economies and laws which both still sort of use the US dollar (e.g. Seattle would import a lot of USD through corporations, say) is part of the beginning.
Remember that with the Roman Empire, the Catholic Church and Feudal lords carried on many of the legal structures even after the Roman Empire stopped being able to be said to be a single entity. Systems of debt peonage carried over, the division between "arable land owning military citizen" and "slave/debt peon/non-citizen" carried over to "lord" and "peasant". The Catholic Church maintained Imperial divinity even though it was now a pope instead of an Emperor. Not with the exact same things, but that's what I imagine US Empire will look like in a few hundred years.
This, of course, is alongside the tightening of Capitalist contradictions. Rich get richer even as profits get squeezed (until mono-oligopolies spread around the world), poor get poorer and more numerous and desperate. But the legal and nationalist concept of "The United States of America" I think will look like the above. Also, the US Military and intelligence apparatuses will continue to defend Capital since that's why they exist.
I can never take anyone seriously who talks about any of the current geopolitical entities still existing in "hundreds" of years, let alone the already-in-early-collapse US empire specifically. As others have said, collapse is (more often than not) a process, but that process can happen extremely rapidly if the medium it exists in allows for it or even demands it. That medium is global society and it is a vastly different kind of entity now than it was a century ago, even more different than it was before the industrial revolution, and barely comparable to it was around the time the Roman Empire that often erroneously gets used as a metric of comparison. Sometimes people like to refer to how it took more than a century for it, or some of a number of older empires to fall, but they aren't accounting for how different the material conditions are now, such as the conditions that allow for information to travel instantaneously to opposite ends of the globe (to name one obvious example) and how significantly these differences inevitably increase the rate of societal and political change.
The rates of technological, social, and environmental change are all increasing, and not just as a linear increase, it's exponential. By the turn of the next century the world will be entirely unrecognizable from what it is today. Climate change alone will ensure that, with mass migrations (and die-offs) happening on a scale humanity has never seen. That much is unavoidable. It's insane to think the US will still exist in a few hundred years. The face of the planet even, in terms of the biosphere, will be completely different as a result of the ecological collapse wrought by climate change, and some people here think the current unstable political entities will survive that? It never ceases to surprise me when communists, ostensibly with an understanding of historical materialism, fail to get this.
edit: I don't mean to go off on you in particular, keepcarrot, I generally really like your comments. This is just something that bugs me when I see it come up here, in part because it makes me feel like even my fellow comrades don't understand how dire things are now in a way that they weren't in the past and on a scale that wasn't even registered in the past.
Nah, it's ok. It's the way I see it, but I'm not married to it or anything.