Because in days gone by the main business of English politics was holding the multi­national UK together, the majority English suppressed an explicitly English nationalism so as not to provoke the others. Indeed they encouraged and patronised Irish, Welsh and Scottish culture – so long as it did not take a politically separatist form.

This has left English self-consciousness the most uncertain. I endorse a growing paradox: that the English should no longer suppress their Englishness and should see what it means to be both English and British.

Gordon Brown, in his speeches, characterises Britishness in terms of a civic culture: “When taken together, and as they shape the institutions of our country, these values and qualities – being creative, adaptable and outward-looking, our belief in liberty, duty and fair play – add up to a distinctive Britishness that has been manifest throughout our history, and shaped it.”

These are indeed strong values of Britishness, if more narrowly institutional than many commonly think. Britishness needs rounding out with a narrative of the different cultures of three nations, at least, and Northern Ireland and Islam need more empathy than exhortation to abide by a common civic culture.

But this is precisely what Mr Brown does not do. Not merely is there understatement of the balanced nature of the Union, but the examples he gives of our long British tradition of civic values are all English. The myth of Magna Carta’s importance is once again disinterred and nary a word on the Declaration of Arbroath. He invokes Milton, Wordsworth, Burke and Orwell as British rather than, it seems to me, typically English voices. Walter Scott and Robert Burns are ignored, though both were Unionists, powerful voices for a dual not a single identity.

Mr Brown is saying that a heightened Britishness is necessary to hold the Union together rather than simply a rational calculation of mutual advantage. But he is attacking the Scottish National party with the wrong weapon. Confusing “nationalism-as-tradition-and-national-consciousness” with “nationalism-as-separatism”, he plays into their hands. Identity politics may come a poor second to pragmatic worries about disruption and scepticism about the economic benefits of separation.

Politically, of course, he walks a tightrope. British Brown for Middle England is not music to Scottish ears nor does it face squarely the task of persuading English voters to distinguish Englishness from Britishness and be both. Mr Brown’s disappointing mixture of rhetoric, bad history and perhaps political opportunism comes out in a statement drafted for a 2005 conference: “How ‘British’ do we feel? What do we mean by ‘Britishness’? These questions are increasingly important in defining a shared purpose across all of our society. The strength of our communities, the way we understand diversity, the vigour of our public services and our commercial competitiveness all rest on a sense of what ‘Britishness’ is and how it sets shared goals.”

So Britishness must express “a shared purpose” and “shared goals”? And he wants this to be taught in “the new citizenship curriculum”, forgetting that it applies to schools in England only. Such language is like that of the old-fashioned nationalism of central Europe between the wars. But is that really how states hold together, especially in the modern world of a global economy and of all notions of national sovereignty needing to be so qualified as to be almost useless in understanding actual politics?

This idea of national purpose is what Goethe called “a blue rose”. The search for it can prove damaging. Both Baroness Thatcher and Tony Blair have spoken of restoring our sense of national importance, a hangover from the days of empire and the second world war. The only way to box above our declining weight has been, of course, to tie ourselves to the coat-tails of the US. Long ago Dean Acheson, the US statesman, warned that postwar Britain’s only post-imperial “role” could be to rediscover Europe.

I leave you to consider either that our rulers have been playing the wrong kind of game of national purpose and identity politics or that the game is itself mistaken. Perhaps rather than a world role under a pretend world leader, we would be left with ourselves and our partners in Europe. Is that too bad? I think not.

Prof Sir Bernard Crick is a former government adviser on citizenship; his work led to the new requirements for naturalisation. This is an extract from a lecture on Identity Politics this evening at the University of Glasgow