A Field Guide to the British, By Sarah Lyall

Germaine Greer came to the conclusion that "English culture is basically homosexual" after one of her lovers climbed into bed with her and said, "Let's pretend you're dead." Although there may be other explanations for this remark, Sarah Lyall, London correspondent for the New York Times, is too polite to reflect upon such things in morbid detail. Perhaps, as her book is keen to demonstrate, this indicates that having lived here for 13 years she is becoming more British – whatever that means.

The question of Britishness continues to hang in the air like drizzle. When Parliament is sitting it always seems to be there, but is strangely without substance. Some pretend it isn't there at all, some get all hot and bothered trying to get hold of it, as if they are trying to catch the moon in a sieve. British identity is neither English, Scottish, nor Welsh, but all that and less – an unsatisfying and (at present) unsatisfactory amalgam.

Lyall's contribution to the national debate is armchair anthropology gleaned from the newspapers and her bedtime reading. Her book is a history of the Blair years told in newspaper clippings and odd little forays to meet ordinary people going about their daily lives, whether on trains or in bars or shivering behind windbreaks at the seaside. It is compiled from the anecdotal, the apocryphal, "facts too good to check", and the purely fictional (PG Wodehouse, Daphne Du Maurier and Ian Fleming).

It is a ship of fools, a best of British beef-wittedness – rather like having a garrulous dinner party guest who holds all entranced from the end of the table with a sparklingly witty monologue on the gruesome horrors of boarding school and the sexual allure of Margaret Thatcher, the parallel universe of cricket, and the evergreen eccentricities of the class system, the preposterous oafishness of Jeremy Clarkson and the cartoonish tomfoolery of Boris Johnson, risible dentristry, bad hotels, worse food, poor football, the weather – it's pretty much all here. Predictable stuff maybe, but told with such verve and wit that the book deserves a place in every lavatory, loo, or (god forbid) toilet in the country.

There are some terrific old chestnuts included, such as the delicious story about Harold Wilson's Foreign Secretary George Brown, drunk at a reception for Peruvian dignitaries. He approached a guest attired in a crimson frock and asked for a dance. The guest declined: "First, you are drunk. Second, this is not a waltz; it is the Peruvian national anthem. And third, I am not a woman; I am the Cardinal Archbishop of Lima." Yet, despite living here for 13 years, Lyall still doesn't appear to know the difference between Britain and England, describing the 1966 World Cup-winning England football team as "possibly the best thing to have happened to British sport". Scottish international Denis Law actually described the day that England won as "the blackest day of my life". Even commentator Kenneth Wolstenholme complained about the endemic conflation of England with Britain.

It all depends who this book is aimed at. I can't imagine Scots are pleased by the way that "Britons" on the page keep metamorphosing into "the English". But perhaps that is the most English thing of all about Sarah Lyall. Doubtless there is an audience on the other side of the Atlantic who will thrill to the tales of knockabout politics and feral journalism, who always wanted hard evidence that the British have the worst teeth in the world, and who need a transcript of "tampaxgate" handy. In that case I expect that they will keep A Field Guide to the British close by them: probably in the, er, bathroom.

Nick Groom's 'The Union Jack' is published by Atlantic; he is professor of English at Exeter University