The writer is former professor of modern British history at Cambridge. His new book, Mr Churchill’s Profession, will be published by Bloomsbury in 2012.

Nearly everyone agrees that the crisis in Britain’s relations with the European Union has a historic dimension. Some proclaim it all goes back to the Maastricht Treaty 20 years ago, while others talk of the end of 40 years’ work, ever since Britain’s accession to the European Community. If Britain is now alone, then popular invocations of Churchill take us back to alleged parallels more than 70 years ago. Whether this is the end of 200 years of history, as Jonathan Powell argued in the FT ("Cameron has betrayed 200 years of history", December 12), continues to agitate readers of these pages. Such perspectives, however, may be far too short.

After all, it is Charlemagne who is celebrated for establishing a certain idea of Europe. Crowned Emperor by the Pope in 800, he certainly put his stamp on half a continent. Yet though his Carolingian dynasty achieved mastery, its origins had been relatively humble. For the Carolingians had risen under their predecessors, the Merovingians, essentially by doing the dirty work for them, with no grander title than that of major domo or "mayor of the palace". The Merovingian kings were garbed in the trappings of monarchy, but it was the Carolingians who shrewdly grasped the levers of power, as the mighty Bishop of Rome had to recognise.

Just a fable for continental Europeans? The insight that it is not formal titles and institutions that confer power, but power that commands institutional recognition, transcends time and frontiers. Perhaps David Cameron forgot this when he headily suggested, at Brussels last week, that his veto would deny the other 26 leaders any access to the political and judicial organs of the European Union. For if 26 national leaders are intent on co-operation – a big if, perhaps – they will surely find the means of implementing their will, through shadow institutions that could soon become the real institutions. The Berlaymont in Brussels, the imposing official headquarters of the European Union, might become a mausoleum, its dusty corridors paced, like Merovingian monarchs, by lonely British prime ministers, puzzled at how quiet the old palace has become...