The sheer variety of British new writing means that refracting plays through the prism of national identity, as Aleks Sierz’s new book does, feels blinkered Pick a play – any play written in the last decade – and the chances are Aleks Sierz could offer an interpretation about how it refracts national identity. Mike Bartlett’s Cock would be a portrait of an uncertain, indecisive Britain, endlessly caught between two possible futures. Ghost Stories ? Why, the crippling paranoia born of a fragmented society, in which everyone is ultimately alone. And the Rain Falls Down ? What could be more British than obsession with the weather? I’m being facetious, of course. Only one of those examples (Cock) comes from Sierz’s new – and broadly enjoyable – book, Rewriting the Nation: British Theatre Today , a survey of the last 10 years of new writing in the UK. In it, Sierz attempts a working definition of new writing, assesses the health of our new writing culture and pulls together a composite picture of contemporary Britain. It’s a neat reflection of theatre’s uncanny capacity to echo and encapsulate its surrounding society. Often overly neat. Reading Rewriting the Nation, I found myself nagged by the very concept it examines. What, I kept thinking, makes a play a state of the nation play ? How does it mark itself out as such? Watching Cock at the Royal Court last year, it never once occurred to me that Ben Whishaw’s John might be “a metaphor for a nation unsure of itself”. Undoubtedly it tackles sexuality, but it also seemed concerned with generations. Yet if age felt important, why not nationality? After all, I thought of these people as British – sometimes, particularly so – and yet that seems to be secondary, if not irrelevant. Sometimes there’s no room for doubt, if only because the title of a play doesn’t allow for it. A nation can be a play’s constant or protagonist, as in Richard Bean’s England People Very Nice , which focused satirically on waves of immigration into the East End of London, or else its pivot. By placing Englishmen abroad, DC Moore’s The Empire highlights their Englishness, just as Roy Williams does with the England match of Sing Yer Heart Out for the Lads . Other plays are draped in national iconography: Jerusalem, set on St George’s Day, bombards us with English symbols from the off, beginning with a St George’s cross and Hubert Parry’s stirring setting of William Blake. Elsewhere, however, it’s harder to discern. Setting can, but doesn’t necessarily, confer state of the nation status. How crucial is Leeds to Blasted or London to Earthquakes in London? I suspect both could be broadly the same play if set elsewhere, but their stress on setting forces location – and with it, national identity – into the crosshairs. Likewise, while institutions inevitably reflect the society that created and continues to shape them, they can also function as metaphors or microcosms of that society. Michael Billington suggested that Nina Raine’s Tiger Country showed the state of the NHS without reaching beyond to the state of the nation, as does Peter Nichols’s The National Health. I read Mogadishu in terms of its wider political implications, but not John Donnelly’s The Knowledge , even though both are set in schools. Family structures and organisations can exact a similar multiplicity. It seems a cop out to say so, but there’s no way out bar subjective perception. Whether you see a character as a particular individual or representative, as English or simply as human, depends on the angle of approach. That said, though there aren’t strict parameters that identify a state-of-the-nation play, to refract everything through the prism of national identity, as Sierz does, feels singularly blinkered. Theatre Matt Trueman guardian.co.uk