On Wednesday evening a high-level spook I had known vaguely at Oxford, a former Etonian and a Bullingdon Club chum of David Cameron’s, rang me up with interesting findings and a resistible offer. “You’ve been following this Birmingham schools thing, Lee?” “Yes,” I replied. “It’s outrageous. No child should have to go to school in Birmingham.” “Very funny,” said the spook. “But what do you make of it?” “Well, Doug,” I answered, “it appears that where education is concerned, all faiths are equal, but some are more equal than others.” “Don’t be smart, Lee. People’s lives are at risk. This could kick off into a bloody civil war. Luckily, Dave’s got a plan.”

Indeed he had. Like a man distracting his children’s attention from a terrible car crash by pointing at a funny pig, David Cameron had deftly skirted the ideological collapse of the education system by saying all schools had to teach British values, and then disappearing back into his office before anyone had the audacity to ask what that actually meant.

As he monitors all communications of any sort all the time, Doug had noticed that my standup comedy act was much discussed online by the sort of fidgety middle-class liberals inherently sceptical about notions of patriotism. Doug wanted me to fill a gaping hole in an emergency celebrity thinktank in Westminster the following morning, aiming to produce a workable definition of British Values as quickly as possible.

This definition could then be translated into Welsh, Gaelic, Cornish, Polish, Bulgarian, Romanian and Urdu, printed up on massive boards mounted on the front of intimidating armoured personnel carriers, and driven around areas with high immigrant populations by masked gunmen, instructed to shoot on sight anyone who so much as tutted at them.

There was no fee for the focus group, but unlimited Fanta and party eggs were to be provided for all the celebrities, and each of the entertainers was to be given a £4 voucher to spend in the House of Commons bar at the end of the day. The token could not, however, be exchanged for sparkling water or continental beers, which were to be paid for at a till linked directly to an account in Luxembourg, as part of an arrangement organised by the chancellor.

It was not the first time I had been invited to help shore up British national interests. Earlier this year, the famous adventurer Rory Stewart had asked me to be part of a continuous Auld Lang Syne of e-list celebrities, their arms linked along the border in a gesture of Anglo-Scots solidarity. I was to take my place on Adrian’s Wall, joining hands with the Scottish folk singer Dick Gaughan, and a lifesize wash mitt of Archie the Laird of Balamory.

Gaughan, a staunch nationalist, declined, and the foamy Archie mitt became saturated with tepid bathwater and collapsed in on itself, uselessly. Besides which, my own opposition to Scottish independence had by then collapsed too. In the light of Ukip’s success I now rather wished that I too could become independent of Britain and Farage’s bewildering policy void. Nonetheless, anxious to defer bloodshed in my home town of Birmingham, the city of a thousand faiths, I accepted Doug’s offer.

The next morning, Thursday, I found my letter box compromised by a free copy of the Sun newspaper, which was aiming to win new readers. In the wake of Ukip’s success and our forthcoming national football fever, 22m patriotic editions of a special England issue were delivered free to unwitting households all across Britain. Some made landfall in beatnik hipster urban zones such as mine, where the paper was so rarely seen by human eyes that it had assumed a folkloric air, like the sasquatch or the kelpie.

I was to be charged later that day with defining a national identity – Britishness – and the collective good was at stake. Tangentially, the Sun was struggling with a similar conundrum. The paper was trying to define Englishness, through the thoughtful writings of my fellow celebrity columnists James Corden, Tony Parsons, Jeremy Clarkson, Katie Hopkins and Rod Liddle. If anyone could wrestle this age-old problem to the mat it was this dream team of clockwork opinion monkeys. Perhaps I could learn something that would be useful later that day.

For Parsons, the English are “gentle, tolerant … and love animals and freedom… and hate people who aren’t polite”. Parsons’ definition of Englishness sounds like a transcript of the envelope upon which Ricky Gervais worked out his Derek character. Hopkins maintains she’s English because if you cut her to the core her blood’s “red, white and blue”, which presumably means Katie washed her England flag along with a non-colourfast Conservative Party HQ sauna wash mitt. Corden appears in the paper in knitted tie, his face painted with a cross of St George, looking like the Man at C&A version of the Christian soldier who goes crazy and dynamites the Cajun’s shack in Southern Comfort. The image illustrates his column. There is no need to read his column.

A Sgt Pepper-style Sun collage of 117 definitive English people included James Corden, Simon Cowell, Boris Johnson, Michael McIntyre, David Cameron, Jeremy Clarkson, and Nigel Farage, but no Mark E Smith, William Blake, Mary Wollstonecraft, Ted Chippington, or Pauline Black from the Selecter, which my superior version would have boasted. At which point during the preparation of the artwork was Gary Barlow crossed out? When did they realise they’d forgotten to include Rik Mayall, who narrowly escaped this unasked-for honour?

Doubtless the Sun‘s choices exemplify Englishness to someone, but not to me. It was as if ideals of identity were almost entirely subjective. Making David Cameron’s dream of a definition of Britishness a living reality was going to take some doing.

I arrived at Westminster at 8am, ready for a day of defining national identity with the other key British celebrities hurriedly assembled by Cameron’s advisers; Inayat Bunglawala of the Muslim Council of Britain, Judaism’s Rabbi Sachs, television’s June Sarpong, Top Gear‘s Richard Hammond, thought’s Brian Eno, women’s PJ Harvey, history’s David Starkey, comedy’s Leo X Muhammad, Scotland’s Lulu, Northern Ireland’s Van Morrison and Wales’s Gorky’s Zygotic Mynci. Rabbi Sachs embraced each of us in turn at length, weeping; Hammond began sucking hard on a Calippo; Van Morrison took off his wellington. The debate had begun.

Stewart Lee is appearing at the Bloomsbury theatre, London, this Wednesday and Thursday, in Tell Me Something I Don’t Know, a benefit for Arts Emergency, a charity helping students from disadvantaged backgrounds.