I don't think they were relevant in the past either. The British empire may have been similar to the Spanish or Dutch and followed a similar path. These were maritime trade empires in the age of discovery, monopolizing new trade routes.

But, I don't think the Ottoman, Chinese, Arab, Hitite empires give us any predictive information for the longevity of the later ones.

I mean, history does show pretty convincingly that "stuff ends" eventually. It's got some examples for how, they are usually fairly specific and unclear. Europe has been obsessively theorizing about The Fall of Rome for 1500 years. All those musings really tell us about is the people doing the musings. It was because of Debauchery, Christianity, Tyranny, Civil Strife, Monetary Policy, Cultural Purity, Military Discipline etc. etc. depending on who you are.

I bet you can guess that Victorians suspected orgiastic debauchery while Marxists suspected class structure.

This is the first era in history in which we have a complete, unobstructed view of the world. We can communicate instantly with anyone, anywhere. We can share our culture and our ideals instantly with anyone, anywhere. What does this mean for traditional powers? Does it mean they will last longer or die sooner? I don't know the answer to that question. But to suggest that this era is not special is incredibly short-sighted.

They said the same about the clipper ship, I'm sure at some point in time someone thought that smoke signals were a pretty good idea and that now all would be different.

So yes, we can do all this stuff better, faster. It makes for a huge difference in degree and if that difference is large enough by itself it becomes a qualitative difference.

But I think the mistake is to think that a change like that is enough to significantly decrease or increase our ability to build empires or to destroy them because those forces tend to balance out (assuming both sides have roughly equal access to the technology).

That's why none of the other technological advances from the past made a huge difference either, the 'empire' that was expanding brought their technology with them, it became adapted and then was used against them or they simply regressed.

The only times it worked was when the natives were entirely slaughtered or intermixed and those countries typically ended up declaring independence.

Empire building is a losing business in the longer term, and there is no proof to date that a complete and unobstructed view of the world or instant communication are a key element to empire success (or failure).

To compare the Internet with a ship or smoke signals requires a level of ignorance and cognitive dissonance that I simply cannot fathom.

Empire building is about war, pure and simple. Communications lines and information are a tool in the hands of those that wish to build empires and those that wish to bring them down.

But since you're framing the argument in terms of ignorance and such I think I'll bow out here.

but the discussion isnt about building an empire, increasing its land holdings or anything of the sort.

Its about maintaining an empire, which i think is an important distinction.

I dont see the US waging war against anyone who is trying to dethrone them as a superpower. The ways that other countries are trying to dethrone the US are much more economic.

Economic war can be waged over the internet quite well, without any ships or smoke signals.

Why do you assume only external threats? Keep going with the extreme (and accelerating) inequality and there will be a breakdown. Look at your debt levels. Look at internal issues. Education/healthcare hyperinflation. Disrepair of infrastructure. Massive incanceration rate. Exploitative employment practices. Wage stagnation. Police brutality. Corruption/wastage in public projects (Big dig, for example, hyperoverpriced subway) Do you think it can be fixed in time? Is it even possible to have a factual, problem oriented discussion, when both sides of political discourse are too tangled into ideology to try and solve the real, underlying problems? How long is it before it all boils over? And lets not even go to the actual military might - a lot of your current procurement programs are completely dysfunctional: the helicopter contract, Bradley controversy, F-35 fiasco, Ford carriers issues, the LCS joke, Raptor cancellation, just from the top.