Ashley Gilbertson's photographs from Iraq capture the brutal, tragic and sometimes surreal moments of the war. He talks to Adam Harvey

Between wars, combat photographer Ashley Gilbertson needs to make a buck. So in New York earlier this month, he accepted a magazine assignment to shoot author Peter Carey.

Close-cropped, with rough edges barely softened by an ever-present cashmere scarf, the 29-year-old Gilbertson is a battered veteran of dusty trouble zones such as Baghdad, Falluja, Mosul, Kabul and Kosovo. Artsy writer's lofts aren't his natural working environment. So he strode into Carey's SoHo apartment and told the two-time Booker winner how this was going to work.

"Right, the monkeys on the picture desk want it done like this," explained the New York-based Australian, in an accent that got lost somewhere between Melbourne and Madison Avenue. "Forget about that. We're going to do this, this and this, and then we can sit down together and decide what photos we're going to send back to them."

Carey was silent for a moment. "That's the spirit," said the author, and the photoshoot later spilled into a bar, where Gilbertson and Carey on compared publishing scars.

Smooth as sandpaper, Gilbertson has always got on better with his subjects than his bosses. As a Baghdad-based photographer with the New York Times, his best memories of Iraq are of the weeks spent embedded with marines, waiting for something to happen. Gilbertson was 24 when he first landed in the country in 2002 and didn't have any problems tuning into the frequency of the young Americans.

"Basically it was sitting around, complaining about waiting. As an Australian, I'm a professional complainer anyway - there's no problem if you're not complaining about it," says the chain-smoking, hard-drinking, one-time philosophy student. "Complaining about anything: you'd be bitching about Britney, about what a cracker she is, someone would say, 'Shut up man, I'm from a trailer-park', and that'd start them off.

"You can almost imagine you're back home having the same chat in the bar. That's when it truly becomes heartbreaking."

Ten of the soldiers seen in Gilbertson's newly-published book of Iraq photographs, Whiskey Tango Foxtrot, died during the operations he covered.

Some of them were killed in the moments after Gilbertson took their picture. One of them, 22-year-old Lance Cpl William Miller, from Pearland, Texas, was shot a step in front of him while clearing a mosque's minaret in Falluja so Gilbertson could take a photograph. Gilbertson was drenched in so much of Miller's blood that he at first thought the bullet had pierced the marine's Camelback water reservoir. It had hit his head.

Gilbertson knew most of those dead marines well. In the Falluja operation, which remains the bloodiest encounter of an occupation that will soon be five years long, he was embedded with a marine company spearheading Operation Phantom Fury. The US attempt to wrest back control of the insurgent-held city ended nine days later with 95 US soldiers dead and some 2,000 wounded. Seven of the marines accompanying Gilbertson died.

HIS PHOTOGRAPHS OF Falluja earned him one of photography's most prestigious gongs, the Robert Capa Gold Medal Award from the US Overseas Press Club, which has previously been won by legendary war photographers such as James Nachtwey, Tim Page, Horst Faas and Eddie Adams. They all used the same simple method.

"You need to be with the first unit," says Gilbertson. "If you get there 45 minutes later, it's all over."

He made a terrifying entrance into Falluja's mean streets with Bravo company of the First Battalion, Eight Marines.

"There's this huge six-lane street," says Gilbertson. "On the other side of the street was this cultural centre, which was supposed to be a staging point of the insurgency. The unit is freaking out at this house across the street, and they had to cross the street to get to it. If you can imagine somebody throwing hundreds of firecrackers to the left, to the right, front and back, and then running through them, and then imagine every explosion is a bullet being shot at you, that's what it was like. I saw these guys streaming out of the gate then falling down, getting shot.

"The last guy to go is screaming, 'Third platoon - go!' and looked at me as he said it. What do you do? You run.

"You can see tracer rounds, feel them hitting the road, feel every muscle as you run out into it. Time moves slow, you're running so fast to get off it. It was without a doubt, the most dangerous thing I have ever done."

Gilbertson didn't even take a frame until he was across to the other side. Some of his strongest photographs were taken a few minutes later, once the marines had taken the cultural centre.

Whiskey Tango Foxtrot (that's the US military's radio code for "what the f**k?") is a sharp-focused memoir that follows the law laid down by the father of combat photojournalism, Robert Capa - "If your pictures aren't good enough, you're not close enough" - and it's the proximity that sets his images apart. The troops trusted him, and he saw things that others didn't - some of his most famous images include that of a soldier gleefully sliding down a banister in one of Saddam's palaces with a rifle slung across his chest, and one of units interrogating suspects with their fists and feet.

GILBERTSON WON HIS stripes as a photographer by getting closer than the others. He paid his own way into Iraq in 2002, and before he was picked up by the New York Times his first paying gig in the country was from a German TV crew who weren't allowed out at night. They'd heard Gilbertson was seeing some action, so they gave him their video camera to bring back pictures of gunfire and explosions.

Gilbertson acknowledges that there are professional dangers to getting too close. Being shot is only one of them. In Samarra, he watched a translator for US troops threaten a suspect at knifepoint - and didn't take a frame. Afterwards, he was disgusted with himself. "I had grown too close to the platoon and had unintentionally protected them. I was incredibly upset," he says.

Gilbertson went to Iraq seven times between 2002 and 2007, returning even after Lance Cpl Miller's death. Gilbertson blames himself for that, and has since spent time in the company of therapists and bartenders. Nevertheless, he's planning another excursion to the New York Times's fortified Baghdad compound this year.

In one sense, it's a foolish mission - outside the Green Zone it's become too dangerous for western photographers to work effectively. Jobs are done fast, sometimes with the photographer travelling to the assignment in the boot of a car, to prevent insurgents from getting word that one is on the scene.

"I should be scaling back," he says. "But I have so much personally invested in this story. I want to go back. I want to see Iraq in peace, even if that means an Iraq that's split into three countries. I want to see Iraqis not trying to kill each other, or trying to kill me."

Whiskey Tango Foxtrot: A Photographer's Chronicle of the Iraq War is published by the University of Chicago Press