Before Dr Spock, before What To Expect When You're Expecting, before our era of a thousand Joy of Parenting manuals and mommy memoirs, there was Albert Camus. 

Part of what Camus did in The Outsider was to challenge the idea that the bond between parents and children, mother and son, was automatic, natural, loving. Lionel

Shriver's Kevin Khatchadourian could be the outsider's legitimate son.

Ever since it won the Orange Prize, the adjective most often used to describe We Need To Talk About Kevin is 'controversial'. It's a reassuring label to stick on a book that takes on 21st century shibboleths and taboos: it allows readers to back off, to stay at a safe distance from a writer who unleashes her enormous talent on the exploration of the dangers and hidden traps of intimacy.

The voice that draws us in belongs to Eva Khatchadourian, successful entrepreneur, indefatigable traveller, loving wife, sceptical mother, survivor. 

The things she's survived are many: foreign countries, the destruction of her marriage, the festering doubts of a woman who has no 'maternal heat' to see her through the tribulations of motherhood, the birth of a son who, to her, is impossibly alien.

Her story unfolds through the missives -- urgent, wry, introspective, devastatingly honest -- that she writes to her husband Franklin, after their 15-year-old son Kevin took down seven classmates and two others in a Columbine-style massacre. 

'I am never able to get the full story inside me. It's larger than I am,' writes Eva in the aftermath. To tell it, she has to return to territory that she once considered absolutely familiar; like her travels for A Wing And A Prayer, the guidebook imprint she owns, she must revisit the tedium of travelling to the exotic (where everything begins to look familiar after a while) while praying that for once, the journey will be a new, astonishing exploration.

Eva emerges as a forceful, bright woman whose tragedy is that she cannot soften the edges of her vision; she lacks the ability to tell herself the lies that take so many men and women through the flawed intimacy of marriage, parenting and the strange countries that lie beyond. 

We Need To Talk About Kevin explodes several myths (one of them is that a book about school shootings can't be hilariously funny). For Eva, motherhood is not the natural, inevitable life journey it's made out to be by modern parenting gurus; pregnancy feels like being inhabited, as she puts it, by an alien even as it forces her to live, like a child, by the rules of other people. 

Kevin is not an easy child to love; and love is not an emotion that Eva can dispense with ease either. From her perspective, Kevin is a terrifying bright child who blends anomie and apathy with an intelligence that he uses to manipulate the world.

Franklin, Eva's husband, holds their increasingly strained household together with blind optimism and a belief, unfounded but poignantly deep, in the power of familial love.

Lionel Shriver's prose packs an intensity that few contemporary writers today can match. We Need To Talk About Kevin may start with the simplest of units, the family, but it's a hugely ambitious exploration of violence, love and what lies beneath the surface of America.

'I seem finally to be learning what you were always trying to teach me,' Eva writes to Franklin, 'that my own country is as exotic and even as perilous as Algeria.'

Shriver will spare the reader nothing. There are no easy answers to the question America asks itself every time there's another school shooting, another kid armed with a crossbow or a gun locking the doors of the gym before he takes out his classmates.

There are no easy ways to look at parenting and motherhood with clarity in an age where these are the last shibboleths we hold on to, the last bastions of certainty in which we can deposit our faith. 

We Need To Talk About Kevin explores parenting, and modern America, and motherhood, and the difference between home and away, but it's really, like all great novels, about grappling with the beauty and ineradicable strangeness of the human condition. It demands more of the reader than any other book published this year; and that's why it must be read.