After he decided to become a professional writer, Ben Fountain's debut novel took a long, long time in coming.

But it's been worth the wait. And I'd hazard a guess that Billy Lynn's Long Halftime Walk will eventually be regarded as one of the defining novels of its age.

It takes place on a Thanksgiving weekend during the Bush era. Nineteen-year-old Billy Lynn and the surviving members of "Bravo Squad" are being wheeled around the USA as heroes after their victory in a battle against Iraqi insurgents. We join them in a Texas football stadium, where they are scheduled to accompany Destiny's Child on stage as part of the half-time entertainment.

Everywhere Bravo Squad go, people want to shake their hands and utter platitudes that seem ripped straight from the mouths of Fox News anchormen until they turn to verbal mush in Billy's mind: "nina leven", "currj", "double y'im dees".

In tow is Arthur, a film producer who's trying to hammer out a deal for a movie about their experiences. He reports delightedly that Hilary Swank is keen, but won't commit to the part until a studio commits, and no studio will commit until Swank does. Bravo Squad's appreciation of this paradox is a deliberate echo of Yossarian's "respectful whistle" when he is told the meaning of Catch-22.

But, despite the direct reference, this is a different kind of novel. Rather than highlight the absurdity of war again, Fountain is more concerned with the seamless merging of the propaganda and entertainment industries, which has become a higher and darker art than Joseph Heller could have foreseen.

The alienation of the soldier returning from war to people who haven't a hope of understanding what he's been through is familiar enough to be a cliche. Fountain has rejuvenated it with his critique, but hasn't forgotten the human element: Billy's sister pleading with him not to go back to Iraq; his yearning to make some kind of emotional contact before he's shipped out again; the hollow feeling left by the sergeant who didn't make it home alive. It's satire with a heart, a dazzlingly, sharply written novel which seems to crystallise a moment in time.

BILLY LYNN'S LONG HALFTIME WALK

Ben Fountain

Canongate, £8.99