John Updike novels need little action or showy language. His best tick along at an even, assured pace, allowing him to register every colour in a scene as he passes through. However, Updike obscures the vista in his 21st novel by building a thriller on top of it and too often obscuring the reader's window to shove his views on other cultures and generations.

As a thriller, Terrorist is spare and simple. It's so taut that most readers should see the twists pages in advance. If not, Updike's ruminations usually give the game away. But when they're not orchestrating clumsy coincidences to kick the plot along, those ruminations on the US occasionally amount to classic Updike.

Ahmad Mulloy is a teenager in the fictional New Jersey city of New Prospect. He has lived with his Irish-American mother, a nurse's aide, all his life, but is drawn to Islam by thoughts of the Egyptian father who abandoned him. Smart and hardworking, Ahmad rejects his shot at university and, on the advice of his imam, becomes a truck driver for a furniture business owned by a Lebanese family. Charlie, the son of the owner, joins him on deliveries, sparking his imagination with talk of George Washington as a terrorist fighting the British in the nearby countryside.

Ahmad is sharper than the average teenager. His Muslim learning lets him see through the lazy consumerism of his peers. But the character often gets ahead of who he should be. Updike seems to lose any sense of the modern teenager and drifts into mawkishly geriatric sneering at American pop culture, the Christian girl Ahmad is attracted to and her thug boyfriend, Tylenol. The rest of the time Updike uses him as a hollow vessel who mouths the author's caustic reduction of his homeland.

Ahmad can forensically untangle America's faults, but fails to work out that he's being groomed as a suicide bomber. Updike skips over the chance to explore the complexities behind the choice to kill and be killed for God.

The only character who suspects what every reader will guess is Ahmad's school counsellor, Jack Levy, a 63-year-old lapsed Jew. While Updike struggles to get inside 21st-century youth and Islam, he's comfortable with Levy, a bitterly wise suburbanite, sexually energetic, but slowed by guilt. Levy could be the cousin of Updike's best-known character, Rabbit Angstrom.

Updike finds Levy's voice and conveys his makeup in the best 15 pages of Terrorist. Unable to sleep, Levy ponders the decline of his city's industries and bubbling suburbs. 'Houses have compressed into housing, squeezed closer together by rising land costs and subdivision. Where within his memory back and side yards had once included flowering trees and vegetable gardens, clotheslines and swing sets, now a few scruffy brushes fight for carbon dioxide and damp soil between concrete walks and asphalt parking spaces stolen from what had been generous margins of grass.'

Updike's failure to avoid his standard props - sex and religion in the American suburbs - is highlighted when they surface throughout Terrorist and wind up keeping the novel afloat.