A few years ago, I heard an after-dinner speech from a European statesman, a person who has played a leading role not only in the political life of his own country but in the councils of the EU. The speaker that evening lauded, to general agreement, Europe’s values — its culture, its solidarity — and the quality of its institutions. He went on to stress the need for the unio to propagate these values and institutions more widely.

The discomfiture I felt was shared by some of those sitting with me at the table. My problem was that I could have put similar words into the mouths of some of the most unpleasant figures in world history. The EU that the speaker described was an imperialist project. Those who proclaimed the British empire used to sing: “Wider still, and wider, may thy bounds be set. God who made thee mighty, make thee mightier yet.” Britons may still sing “Land of Hope and Glory” but they no longer take the words seriously. Yet the expansion of the EU embraced a similar vision.

For the builders of modern Europe, wider unio has been as important as closer unio. Greece was hastily admitted in the hope of sustaining its fragile democracy after the end of military rule; Spain and Portugal followed soon after. Every post-communist state with passably honest and democratic institutions, and some without, has secured admission. The ambitious project of creating monetary unio between France and Germany was extended, by lowering admission standards, to include most EU members. The principal qualification for membership of a European club has been the desire to join.

Of course, there are big differences between the Europe of the 21st century and the empires of the 19th and 20th: notably, traditional imperialists did not seek the consent of those they colonised and they suppressed most forms of democratic expression. Yet Greeks today might not perceive these differences as being particularly large.

So the question is whether, like so many imperialist projects throughout history, the European project has stretched its territorial boundaries beyond the limits it can plausibly sustain. That question is highlighted by the two existential problems the EU faces today: the geopolitical confrontation with Russia, and the troubled relationship between peripheral economies and the eurozone.

The boundaries of western Europe have been pushed as far east as at any time in history, save for the best forgotten precedent of the Nazi occupation of most of the continent in 1941-42. The Ukraine crisis tests how far implied promises of political, economic and ultimately military support in that extension will be maintained when called on. The Baltic states have reasonable cause to feel nervous about the solidity of the commitment of their new allies.

Few people can now doubt that it was a mistake to let Greece join the euro in the first place. And this is not just a matter of economics — the fudged data, profligate spending and unpayable debts. The central Greek problem is that the country’s political institutions are not sufficiently mature to effect competent administration or economic management, or to engage in a responsible manner with the institutions of western Europe. And Greece is not the only member state of the EU to which that critique could be applied.