“Every empire creates external forces that end in its destruction.”

I have argued that the Roman Empire did not change, but rather collapsed. Why is this difference important?

Because the idea of ​​“transformation” mitigates what was in fact an accelerating collapse. Rome was experiencing internal tensions, but not ones that could destroy such a developed system. Crucially, the empire profoundly modified its neighbors. Roman globalization created new political structures: groups that did not exist before. The Visigoths, for example, are not a continuation of ancient peoples, but rather a political product of the fifth century that emerged within Roman territory. This means that the collapse did not come from an internal defect, but from the transformation that Rome caused in the environment. The Empire has unwittingly created those who would bring it down.

Do empires fall due to external pressures more than their internal weakness?

Depends on. There are empires, such as the Carolingian Empire, that disintegrated due to the extreme weakness of the centre. But the Roman empires, or the great modern empires, are something else: extremely powerful, long-lasting structures that profoundly transformed their environment. My co-author and I argue that empires that last for centuries—like Rome or the modern Western Bloc—eventually end in their downfall. Not because someone is attacking them from the outside, but because their success creates new forces around them. External pressures do not arise out of nowhere: they are a product of the imperial system itself. Empires always think they are different. But what history shows is that the more their neighbors transform, the harder it is for them to remain as they were. That is the moment when they discover that they no longer control the world, but that the world has transformed them.

Will this happen today with the United States and China?

Yes, and not necessarily in the form of hostility. Empires generate alternative centers of power. In the case of the United States, China is one of them. But this relationship does not necessarily have to be war: it can be a relationship of competition, tension, or even cooperation. The creation of new powers simply means that the empire can no longer control its environment as it once did. What we are seeing now is a renegotiation of the global balance, not the end of globalization.

Do you believe in the “Thucydides Trap” between the United States and China?

never. Politicians can do very stupid things, but there is no fate that condemns great powers to confront each other. The Taiwan issue is sensitive, but it does not mean that there are irreconcilable vital interests. What is true is that politicians tend to think in the short term. They need to win next year’s election, not the next 20. This has been the case since the Roman Empire: immediate decisions trump strategic decisions. This short-sightedness can lead to conflict, but it is not inevitable.

What historical episode reminds you most of the conflict between Washington and Beijing?

The confrontation between Persia and the Eastern Roman Empire in the sixth and seventh centuries. For more than a century, the two powers cooperated, avoiding wars out of pure pragmatism. Then, for political reasons, they decided to do just the opposite: fight for everything. The result: half a century of total war that destroyed them both. Only a quarter of the Byzantine Empire survived that disaster. It’s a frightening example of how bad decisions can turn manageable tensions into disasters. That’s why I worry that the United States and China will one day choose to do something really stupid.

What does the fall of the Soviet empire teach us?

These empires also collapse due to their comparison with abroad. The Soviet Union fell because Gorbachev lost confidence in the regime’s ability to survive while watching the West flourish. The satellite societies – East Germany, Hungary, and Czechoslovakia – could see the difference with their own eyes. It was unsustainable. On the other hand, Putin chose brute force. But its war in Ukraine shows that this model has been exhausted. Internal pressures within Russia are enormous, despite propaganda saying otherwise. It’s the old imperial response: deny reality until it crushes you.

You insist on contingency: that nothing is inevitable until it happens. Could this apply to the United States?

naturally. History does not advance by fate, but by decisions. The hardest thing about writing history is understanding what real options existed. There are always alternatives. Just because something happened doesn’t mean it couldn’t be different. The same thing happens in politics: we have to distinguish between what is desirable and what is possible. History is not destiny. Empires fall not because they “must fall,” but because their leaders make concrete decisions that lead to their collapse.

He worked in the British Treasury. Are we facing the end of globalization?

No, what we see is a transfer process. The tectonic plates of the global economy have already moved. There is no turning back. What happened was that globalization primarily benefited one part of society – the urban and financial elites – while the industrial working class became poorer. This imbalance explains phenomena such as Trump or Brexit. Economic empires also collapse when part of their population ceases to believe in the promises of the system. Every imperial system ends up generating inequality between its core and its surroundings. When those around them feel betrayed, the system falters.

Do we need more economists or more politicians?

We need economists who understand history. It is not enough to look at GDP: you have to see how it is distributed. We need politicians who can think beyond the next election cycle. In Europe, the biggest problem will be population aging. Our welfare state pension systems were conceived in the 1940s, when life expectancy was barely three or four years beyond retirement. Citizens today live twenty years longer and need health care throughout that period. The financial model did not adapt to this reality. It is a clear example of how political systems can become captive to their own victories: longevity, which constitutes a social success, turns into a financial challenge. We are drowning in debt to maintain a system that no longer fits today’s demographics. No one wants to say it, but that is the uncomfortable truth of our mature democracies. This is the kind of problem that could destabilize even a modern empire.

Is there still a link between economics and imperial power?

naturally. Each empire is, in essence, a resource distribution system: it decides who benefits from the exchange and who is excluded. Rome was not just a military apparatus, but a redistribution mechanism. When this redistribution process becomes unbalanced – when many lose and few win – the consensus collapses. The same thing is happening today with global capitalism. Economic imbalances are the new “savages” pressing the limits of the system.

In a post-truth era, what role remains for history?

History must preserve the accuracy of the facts without abandoning the plurality of viewpoints. Not everything is relative: There are verifiable facts — for example, Tylenol does not cause autism — but there are also facts from experience. The same event can be experienced in opposite ways by different groups. The historian’s task is to integrate those voices into a common narrative without weakening factual accuracy. Defending the truth does not mean imposing a single version, but rather recognizing the complexity of reality.

Many analysts today speak of a “multipolar century.” Do you think empires can survive in a world where power is increasingly dispersed?

I think the term “multipolarity” describes the current moment well, but I don’t think it’s new. Rome also experienced multipolar phases, just like the European powers in the nineteenth century or the Cold War in the twentieth century. The question is not whether there are several poles, but rather whether these poles are able to accept the fact that they are no longer able to impose their rules unilaterally. Empires can survive in a multipolar world, but only if they abandon the fantasy of absolute control. The hegemony of the twentieth century will not return. What can exist is leadership capacity: coordinating, influencing, and setting standards. The United States may remain the hegemon, but it will not be the only power. Multipolarity does not destroy empires in itself; What destroys them is their inability to adapt to it. In this sense, the greatest danger facing the Empire is to continue to believe that it is necessary when the world has already changed around it.