Arkady Babchenko didn't write about fighting in Chechnya to make his name as an author, nor to mount a political attack against Russia's rulers. He wrote to recover.

Sitting in a swanky London member's club, he seems perfectly at ease, and as comfortable in conversation as you'd expect a successful print and TV journalist to be. He pops out for a cigarette, but there is no anxious chaining and he drinks only one small beer as we talk. His fingernails are unchewed. But his settled demeanour is clearly something he's had to struggle for after leaving military service.

"Writing was the only thing that helped," he says of the months following his demob. "If I hadn't started writing, I might have lost myself to drink. It was the only real cure. When a person comes back from war, from prison, from any extreme situation, he has to get it out from inside himself. The whole horrific experience - he needs to vent it.

"In Moscow people didn't want to know. So I started to write."

What poured out of him - at night, at work, on the metro - is an unflinchingly un-macho record. No comforting heroes or villains; no familiar arc of near-defeat and triumph-against-the-odds. Instead Babchenko presents us with a relentless account of fear, boredom, confusion, filth, cold, disease, hunger, thirst and lingering dread - a world that feels far removed from the gold-embossed bestselling accounts of square-jawed British or American ex-soldiers.

"I never thought it would be published," he admits. "It's all notes, a rough draft. I didn't think how to make it beautiful to read. I didn't think about how I was writing. I just wrote how I wanted to write."

These notes became One Soldier's War in Chechnya, his memoir of the Chechen conflict which was published in the UK earlier this month by Portobello Books (translated by Nick Allen). As a book, it not only tallies with growing western dismay about life in Russia, but has also earned Babchenko critical comparisons with Joseph Heller's Catch-22 and Tolstoy's early stories about Russia's 19th century Caucasus wars.

Babchenko's background is Muscovite "working intelligentsia": only child, mother a teacher, father an engineer. They were poor, but so was nearly everyone, especially people who relied on the disintegrating state for their pay packets. He was a normal teenager (if there is such a thing) who liked normal teenage things. But he also loved books: his favourite subject was war and his favourite book was Erich Paul Remark's All Quiet on the Western Front.

In the 1990s every young man in Russia potentially faced two years' military service (since cut to one). Babchenko hit conscript age when Mother Russia, in the guise of Boris Yeltsin, was sending her sons south to try to prevent Chechen secession. He did not need to go: he was at university, which buys time; and if time isn't enough a bribe can usually buy exemption.

"But I didn't want to defer," he says. "I can't remember why ... youthful romantika maybe. Or maybe I'd read too much Remark. Of course I'd just as happily not have served. But at the end of the day it's humiliating to get out of it."

The Russian army is a dangerous place, even in peace, even miles from the enemy. One Soldier's War is probably at its most disturbing - and most powerful - when Babchenko describes the younger soldiers cowering in fear of the older men. Drunk, seemingly deranged bullies drag them out of bed, half-kill them, threaten to rape them and then beat them all over again for daring to have black eyes.

But almost as shocking is the inability of Russia to provide even the basics for its soldiers. Babchenko describes soldiers grazing on berries "like moose" or drinking water tainted with rotting human flesh. A soldier, he believes, has the best chance of survival when he no longer cares whether he lives or dies. "If you think 'a year after the war I'll become a writer', then fate will get you - kill you. Fate is a very subtle, a very sensitive system. You need to be as imperceptible as possible. Then maybe it won't touch you."

The stickiest question is why, after eluding fate during the first war, Babchenko went back - voluntarily - for the second.

In 1996 Moscow signed a truce with the rebels, which postponed a final decision on Chechnya's status and left it to continue its metamorphosis into a quasi-independent bandit state. Three years later, however, the newly appointed prime minister, Vladimir Putin, ordered the troops back in, saying he needed to stop Islamic terrorism spilling beyond Chechnya's borders. Babchenko believes his real aim was to cement himself in power.

"The second Chechen war began. The way it drew me back was unbearable. Only my body had come back from the first war. My mind stayed there. My body walked around and looked at this world without understanding it. And seeing as the world didn't accept my body, it returned to where my mind was," he explains. "There was no question whether to go or not to go."

Again he survived. But it seems his greatest piece of luck the second time was to find a way to return home fully - body and soul. For like any addict, Babchenko said, he had to find a way to recover from "adrenaline dependency".

"There's nothing like the density of life in wartime. In an hour you go through so many events, so many life-important events. There's only life or death. Survival - that's the only thing in front of you. Nothing else has any meaning ... life loses its flavour, it becomes boring. And you somehow need to drag yourself back up again. Many people drink, take drugs ... people can only live on the brink."

Babchenko had two crucial routes back: his family and his work as a journalist. "I was lucky to get a hold back on life," he says, "And now I have something to live for."

But even if he can be optimistic for himself, he is pessimistic about Russia. Critics here may value his book, but he is blunt about his chances of it influencing people at home.

"In Russia the book has already been out two years. No effect. No response. Society in Russia at the moment is extremely indifferent, totally unconcerned about everything."

Even Anna Politkovskaya, well known in the west as a campaigning journalist until her ugly murder last year, means very little to Russians.

"She wrote for years, uncovering the sort of crimes that in any normal country would have forced the government to resign - and landed them in court. But we still have them. She wrote and wrote. And what changed? Nothing. Nothing changed."

Nevertheless, Babchenko will continue, as journalist and author, to speak: "That's what I wanted to say: 'I exist. I was in this war. And this is what I saw.'"

· Buy A Soldier's War at the Guardian bookshop for £16.99 including post and packing.