[An empire] requires the crushing of natural nationalist feelings through violence. Which is why the wisest thinkers of the past, from Plato and Aristotle to Niccolò Machiavelli and Montesquieu, were all anti-imperialist (even if the latter two aren’t always recognized as such).
Let’s start with the Greeks, with Xenophon’s Cyropaedia, his highly didactic and not very accurate biography of Cyrus the Great. Xenophon depicts in great detail how, in transforming the small homogenous city-state of Persia into a vast multiethnic empire, Cyrus created a polity that was far larger, mightier, richer, and more technologically advanced than its forerunner. But Xenophon also takes pain to emphasize the costs of this project, which included a decline in good government, the loss of liberty for Persia’s citizens, and an erasure of the individual characters of the empire’s formerly independent but now subservient nations. Since the free spirit of captured nations never entirely dies, their peoples always remain potential threats, so Cyrus had to maintain a massive internal spying and security apparatus, which further curtailed liberty. And if all that weren’t bad enough, on Cyrus’s death the whole system collapsed—illustrating imperialism’s inherent instability. ...
The European Union provides the most illustrative example. Every member state consented to join through some formal mechanism—typically, a legislative vote or a referendum. But further consolidation was often highly contested, with parliamentary votes or referendums frequently coming very close—as in France’s “petit oui” to the Maastricht Treaty creating the EU in 1992—or else rejected—as in the case of Denmark that same year, when the government then resubmitted the question to the electorate after making cosmetic changes to ensure its wanted result. This doesn’t end up sounding like consent in the meaningful sense of the word.
Opposition within Europe is apparent already even as the EU remains a proto-imperial body, and not just with the British who are struggling to carry out Brexit as voters requested and as the government promised to obey (although the elites assumed the vote would be to remain in the EU).
And if the EU elites are to create an "ever closer union" as they say, it will require ever more repression of member nations and their people. We'll see if the EU and their supporters in Britain repress the will of the British people (however narrowly it was expressed, that was the deal preceding the referendum).
An imperial EU that suppresses its people will have more in common with Russia; and the need to hold the EU empire together will lead the EU to focus more on internal threats than external threats from Russia. Russia and the EU might even be natural imperial allies who each fear their own people more than each other.
Or both might think a non-aggression pact is the best course of action in the belief that the other empire will falter from other threats. Europe might think China will crush Russia while Russia might think that unassimilated minorities that grow in numbers in Europe will cripple the EU.
And honestly, the Russians have far more experience running an empire. After the collapses from 1989 to 1991, Russia might have shrunk enough to keep their rump empire longer than the new EU empire with that experience still fresh in Russian minds and with so many unhappy people now out of that empire.
And when the EU collapses as the Persian Empire did, the weakened nation-states that once made up Europe will be unable to stand on their own. The empire might not be able to govern, but it can kill the habits and structure of state governance. And then Russia will have the opportunity to move west again. It has always been ludicrous to argue that Russia would fear the supposed might of a united EU as if that would be more dangerous to Russian ambitions for conquest than the American-led NATO.
The article is mostly about Trump's view of nationalism as the best way to organize the world and his foreign policy based on that. Perhaps that is all true, although describing a doctrine may be premature and simply creating a framework around a few data points of Trump's actions and views.
I found the article's contrast with an imperial mindset that the EU elites clearly have is more grounded in the actions of those people.