Matty Roth, a young photojournalism trainee, is taking his first trip into a war zone with the famous (and famously objectionable) Viktor Ferguson of the Liberty News Network. But soon after their helicopter lands, the team comes under attack. Matty is forced to watch, helplessly, as the chopper - and Ferguson - take off without him, only to be blown out of the sky seconds later, leaving Matty, lost and alone, in an urban no man's land. Baghdad? No - Manhattan Island, otherwise known as the DMZ.

This is the explosive opening of a comic book series, also named DMZ, by New Yorker Brian Wood, and it's the pre-eminent example of a growing fashion for comics and graphic novels about, or inspired by, the Iraq war. DMZ began life in 2005, but next month it comes of age with the publication of a new collected edition. In it, Wood tells the story of a war-ravaged city through Matty Roth's eyes, as the stranded journalist comes to know and love the DMZ and its inhabitants. The setting is New York, following a hazily explained second American civil war; but, of course, it's also a sideways representation of another horribly real urban battleground.

"I started to develop DMZ shortly after the Iraq war began in 2003," Wood explains. "I remember thinking 'I'd better get this book off the ground and running fast, because the war's gonna end soon.' My editor was scared that the subject matter would be old news. Of course, we were completely wrong. When the book came out I was worried that I might get hate mail, or people telling me I was un-American. But by the time the book actually hit the stands, most people were on the same page; the public was against the war. Soon, a lot of other graphic novels critiquing the war started to come out; now it's like we're preaching to the choir."

Today's broad countercultural coalition in the US is often motivated by frustration at the news coverage of the Iraq conflict and its aftermath from traditional media outlets. In such a climate, comic books thrive by reflecting the public bad mood, and they remain streets ahead of many of their rivals in the creative industries. While authors and filmmakers have taken their time preparing fictional responses to the war, comics are a relatively immediate form. In theory, says Wood, "you can write and draw a comic and see it on the stands three months later. A movie can take years."

"Mainstream comics were targeted at children for a long time," says Adam Rogers, head of comics at Forbidden Planet, London's biggest comics retailer. "But as time has gone on, the people who were reading comics began writing them, and now they're producing stories for themselves and people in their own age groups. Big publishers like Marvel and DC have spawned secondary sub-companies that allow their creators to produce stuff that wouldn't normally be acceptable for their mainstream titles. Marvel has Icon and DC has Vertigo, which publishes DMZ."

Marvel's traditional titles seem to have hit a little wide of the mark when dealing with the so-called "war on terror". On the cover of the first issue of Captain America in 1941, Marvel (then known as Timely Comics) had its patriotic frontman socking Hitler square on the jaw. In the months prior to Pearl Harbor, this was a bold and prescient statement. But when Marvel sent the Captain to Afghanistan in 2002, the terrorist-baiting storyline was met with derision and dismay by many readers. In a world where the horrors of war are televised every day, the idea of a spandex-clad superhero hunting Osama Bin Laden or his surrogates lacks the necessary subtlety.

Paul Gambaccini, the DJ and comics connoisseur, was disappointed by the response of the major publishers to the Iraq war. "It's tough for DC and Marvel, because they don't want to damage their relationships with the government," Gambaccini explains. "After all, DC is owned by Time Warner, which also owns CNN. In the 1960s, Iron Man was a risky move for Marvel because he was their only character who was at all conservative. But now Marvel is a very conservative company.

"On the other hand, the creatives would only wish to tell anti-war tales, because surely at least 90 per cent of the creatives were against the war. That's why many of the books that deal with Iraq are independently produced. Vertigo is enough of a separate entity [for DMZ not to be seen as a DC title]. Unfortunately, the failure of mainstream comics to lead on this issue is just a symptom of the extent to which the American media were co-opted into supporting the war. Now, of course, they all look stupid. But that's because they were stupid."

Another Marvel contribution to the Iraq war genre is Combat Zone, a collection of true stories of army life from the experience of embedded journalist Karl Zinsmeister. Straight-faced conservative Zinsmeister, who later became President Bush's top domestic policy adviser, produced a graphic novel that showed his GI subjects in a uniformly heroic light, with one member of the central platoon eventually making the ultimate sacrifice for his buddies.

Combat Zone is in the same tradition as the tales of derring-do that once populated the pages of Commando, Our Army at War, and Sgt Rock, titles that dealt with soldiery during and after the two world wars. But even today's teenagers are well aware that this gung-ho glorification of combat is far from the whole truth, and publishers are responding accordingly. DC, for instance, is home to a satirical take on life in the war zone called Army @ Love, which is set in the fictional "Afbaghistan" and features copious amounts of Pentagon-sanctioned battlefield sex.

"We still stock collections of the old Commando comics," explains Rogers, "but they're very much propaganda, glorifying the destruction of the enemy. New writers are producing more complex work, like Garth Ennis, who has written a series called War Stories set during the Second World War. It follows different armies. There's one storyline about a German tank crew, for instance, and another about a British bomber crew, and how they each react to the experience of war."

David Axe's War Fix, meanwhile, is a personal account of his six tours as an "embed" in 2005 and 2006. A hard-hitting memoir that deals with his troubling addiction to combat, War Fix sees the journalist playing fast and loose with his relationships, his career and his life as he continually goes in search of one last battlefield fix.

While Axe's autobiographical work necessarily features him in a key role, journalists have also become a popular fictional device for comic-book writers in search of an anti-hero. "There's something cool and romantic about a war journalist," says Brian Wood. "They're risking their lives to write stories and take pictures. It's almost heroic. And as a storytelling device, they're great characters to use because they're witnessing everything for the benefit of the reader. They're surrogates for the reader and I think that's why they get used so much. Media now is a massive part of any war. I could turn on the TV right now and find seven channels covering the war. I can watch it like I'd watch any TV show; it almost feels like the two go hand-in-hand now."

In Phantom Jack, Michael San Giacomo's pulpy tale of a reporter who acquires the power of invisibility in an industrial accident, the journalist goes to Iraq in search of a story and his soldier brother, and there discovers buxom beauties and the opportunity to shoot Saddam Hussein in the balls.

Anthony Lappé and Dan Goldman's Shooting War is set in 2011, a time when most of the major news networks have already left Iraq in order to focus on terrorist bombings at home in the US. Jimmy Burns becomes an unwitting media star much like Matty Roth, when one of his popular live video blogs is interrupted by his local branch of Starbucks exploding behind him. The clip thrusts him into the media limelight and he is sent straight to Iraq, an instant war reporter. Soon, Jimmy is being used as a propaganda tool by both his own news network, and an enthusiastic terrorist network calling themselves Sword of Mohammed.

Shooting War is not alone in its unremitting cynicism towards the giants of traditional media. In DMZ, Matty often finds himself in direct conflict with Liberty News, his reluctant employer. Brian Wood admits that the network is a thinly veiled version of Fox News. "Liberty News is a version of Fox News, but I took it a huge step forwards so that Liberty News and the US government are basically the same thing. I intentionally blur that line. Liberty News has soldiers in it; there are guys in uniform in the network rooms. I make a point of confusing the two so that you're not sure where one ends and the other begins. When I came up with that idea, I thought 'this is a stretch, but I'll do it anyway'. But recently the news broke that retired generals and admirals who had been hired by news networks as experts had secretly been on the Pentagon payroll. They're actually paid to be these supposedly 'retired, objective' analysts. It's still a long way off from what I put in the book, but it's a huge step closer."

In DMZ's ill-defined near future, the US has been divided after the civil war between government forces and the insurgent Free States Army, whose soldiers and ideology have conquered a substantial portion of the mainland. Manhattan is caught in the middle, largely inhabited by disaffected non-combatants, subject to violent incursions from both armies, fear of local crime syndicates, and the whims of snipers.

Many elements of the story are deliberately familiar. The sinister Trustwell Corporation undertaking the reconstruction of the city bears more than a passing resemblance to Halliburton. The aftermath of a notorious massacre is based, Wood says, on the fallout from the November 2005 massacre in western Iraqi town of Haditha. The conduct of the war itself is based heavily on Iraq, too. "I rely heavily on Iraq's insurgency model for DMZ," Wood explains. "As Iraq proves, you don't have to be a standing army to oppose a larger force. All an insurgency really has to be is an idea. It doesn't have to win to win, it just has to exist to win. DMZ depicts that kind of battle within the US."

Brian K Vaughan's Pride of Baghdad is arguably the other most successful graphic novel to deal with the war in Iraq - both critically and commercially - though it is in a slightly different tradition from DMZ. Vaughan took as the starting point for his story the news that a pride of lions had escaped from Baghdad zoo during the first weeks of the conflict, only to be shot dead later by US soldiers.

Vaughan's anthropomorphic tale of the lions' travails and their encounters with other animals on the streets of Baghdad has touches of Disney's The Lion King, mixed with the more serious-minded mores of the graphic novel Maus, in which Art Spiegelman recast the Holocaust with the Jews as mice and the Nazis as cats. The lions are initially elated by the unfamiliar feeling of freedom, but soon realise that their new situation is more complex and chaotic than they can cope with.

"With fiction, audiences can watch endless horrors inflicted on human beings, even children," says Vaughan, "but put a dog in danger, and watch people walk out in droves. Similarly, I think it's hard for even the most sympathetic person to truly feel for the civilian victims of foreign wars we see on TV, but strangely, many of us can somehow bridge that emotional gap when it comes to seeing innocent animals suffer. I wanted to write about war from the perspective of noncombatants, and because animals transcend race or creed or nationality, having them be our sole protagonists hopefully allowed us to tell a story that's universally relatable."

Vaughan also writes for Lost, the blockbuster television show with a plane-crash premise that resonates loudly with 9/11, and even numbers an Iraqi war veteran among its protagonists. The writer was living in New York in 2001 and watched the twin towers fall from the roof of his Brooklyn apartment block. "I think comics' response has become more political over the past few years," he says.

"This country [the US] has been understandably frightened since 9/11, and when people are scared, we like to feel like we're surrounded by - and led by - heroes. You don't need to look any further than Bush in his flight suit, Kerry running on his service in Vietnam, or the Terminator being elected governor of California. But do true heroes really exist, or are they just a fiction we create? Over the past 50 years, no medium has explored that question better than comics, so it's only natural that we're returning to it now."

'DMZ Volume 5: The Hidden War' is published by DC/Vertigo, £12.99. 'Pride of Baghdad' is published by Titan Books, £8.99

© 2008 The Independent