Plainly, all empires collapse. The much more interesting and difficult questions are “Why?” and “When?”
As to the why, there is a fair bit be said for the explanation of Joseph Tainter, who in 1988 published The Collapse of Complex Societies. In short, he tested various popular explanations about why civilisations collapse against numerous case studies. The usual explanations of moral decay, disease, innovation et cetera do not stack up very well. Instead, it is when the ER0EI – as applied to social complexity – falls off that an empire is ruined. In large measure, this social complexity manifests itself in the expansion of a class of information producers and analysts who are not involved in primary resource production. Bureaucrats, in other words.
There is a thing called the Vanguard Myth. At the early stages of the development of an empire, there are benefits to be derived from increased levels of complex bureaucracy. But after a while, those benefits tail off, and then become negative. The bureaucrats, of course, do not see that; they see themselves as in the vanguard of development, and forge ahead doing more of what they have previously been doing. Eventually, a tipping point is reached. It is in this zone that the risk – which eventually becomes a certainty – arises of collapse.
What is the topicality of all of this? Well, it is to do with the “When” part of the question. Adapting an old syllogism:
But when? There is a detailed and interesting analysis of this by Gwythian Prins, which is to be found on the Briefings for Brexit website. Gwythian Prins is a bright chap. He taught history and politics at Cambridge for over 20 years, is Emeritus Research Professor at the LSE and since 2016 has been senior academic visiting fellow at the École Spéciale Militaire de Saint-Cyr. For various detailed reasons, which he spells out, he thinks that the collapse of the EU might be coming sooner rather than later. He starts with the Tainter model:
And superimposes the relevant EU landmarks:
Furthermore, his analysis is that when the collapse comes, it will probably not be graceful and gradual, but is more likely to be exponential and quick.
It is an interesting feature of the Brexit debate that, broadly speaking the very brightest and best educated people are in favour of Brexit, there is then a large wedge of people who are moderately bright and moderately well-educated who are against Brexit, and then an even bigger number of people – further down the socio-economic scale – who are in favour of Brexit. To some extent, Prins explains this middle lot – the bureaucrats, one might say – by reference to the Vanguard myth. It is unsurprising that the class of people who benefit most from excessive complexity who are likely to be the most blind to its dangers.
He also makes the remark – which is true enough – that the arguments of those who wish to remain in the EU (the “remainiacs” as Prins calls them) tend to be an intensely emotional aspect of identity politics. When the remainers engage in debate, they are typically far more insulting of the Brexiteers than the other way around. During the campaign leading up to the referendum, the distinguishing features of what was heard from the remain camp were “project fear” and insults addressed at the Brexiteers, who were called ignorant, racist, little Englanders and so forth. But why should this be so? What is it about the Vanguard myth which causes the remainers to be so emotional? To provide an answer for this, Prins goes back to the 19th century, and Edward Tylor’s Primitive Culture. In anthropological terms, a belief in the virtuous superiority of the EU vision of the future is, like other cults, an encapsulated belief system. Prins puts it thus:
So long as its defences are not breached, it has an armour-plated shell. But if a crack of doubt is admitted, it will shatter.
There might be a longer history to all this than the EU. In a sense, the EU stands in a long line of a largely Roman Catholic belief in the unity of Europe. And looking all the way back to Tudor times – the days of Bloody Mary and on to Guy Fawkes and beyond – there is a somewhat fanatical element to be seen.
So what? I guess that might be to answers to that. On the one hand, one might think that if the EU is shortly going to collapse anyway, the question of how quickly and completely we get out is of less importance. Another view might be that we should be well out of the building before the masonry starts to fall.
In the short-term, the prognosis does not look particularly good. The government is dominated by people who don’t really want to leave the EU at all – although they pay lip service to the binding nature of the referendum result. Worse, they are negotiating as if the EU will adopt a reasonable approach the Brexit, which is a hopeless unrealistic expectation, as Yanis Varoufakis has testified. The best that can realistically be hoped for is that the negotiations will collapse, such that the UK leaves the EU without any deal at all. Although there will be some weeping and wailing and gnashing of teeth, things will soon settle down, and the empire’s wish to punish the UK for leaving will soon become subordinated to the disadvantages of a trade war; it will remain the case that the EU will export far more to the UK and the UK exports to the EU.
Meanwhile, Professor Prins’ essay is well worth a read.
 Energy returned on energy invested, viz:
 Wikipedia summarises the analysis thus:
According to Tainter’s Collapse of Complex Societies, societies become more complex as they try to solve problems. Social complexity can be recognized by numerous differentiated and specialised social and economic roles and many mechanisms through which they are coordinated, and by reliance on symbolic and abstract communication, and the existence of a class of information producers and analysts who are not involved in primary resource production. Such complexity requires a substantial “energy” subsidy (meaning the consumption of resources, or other forms of wealth).
When a society confronts a “problem,” such as a shortage of energy, or difficulty in gaining access to it, it tends to create new layers of bureaucracy, infrastructure, or social class to address the challenge. Tainter, who first (ch. 1) identifies seventeen examples of rapid collapse of societies, applies his model to three case studies: The Western Roman Empire, the Maya civilization, and the Chaco culture.
For example, as Roman agricultural output slowly declined and population increased, per-capita energy availability dropped. The Romans “solved” this problem by conquering their neighbours to appropriate their energy surpluses (in concrete forms, as metals, grain, slaves, etc.). However, as the Empire grew, the cost of maintaining communications, garrisons, civil government, etc. grew with it. Eventually, this cost grew so great that any new challenges such as invasions and crop failures could not be solved by the acquisition of more territory.
Intense, authoritarian efforts to maintain cohesion by Domitian and Constantine the Great only led to an ever greater strain on the population. The empire was split into two halves, of which the western soon fragmented into smaller units. The eastern half, being wealthier, was able to survive longer, and did not collapse but instead succumbed slowly and piecemeal, because unlike the western empire it had powerful neighbors able to take advantage of its weakness.
It is often assumed that the collapse of the western Roman Empire was a catastrophe for everyone involved. Tainter points out that it can be seen as a very rational preference of individuals at the time, many of whom were actually better off. Tainter notes that in the west, local populations in many cases greeted the barbarians as liberators.
 Albeit a somewhat unusual one, not least in that its real emperor, Martin Selmayr, is much less visible than its buffoonish frontman Jean-Claude Junker.
José Manuel Barroso, then the President of the Commission, has remarked
Sometimes I like to compare the EU as a creation to the organisation of empire. We have the dimension of empire. What we have is the first non-imperial empire.
 OK, if you are picky, you might call this sort of thing, viz:
- All men are mortal
- Socrates is a man
- Socrates is mortal
 He cites the examples of the DDR and the USSR in 1989 – 91
 There is perhaps some correlation today between Roman Catholicism and prominent reminders like Chris Patten, Tony Blair and the Irish. There are exceptions of course; Jacob Rees-Mogg is a particularly striking example.