Iraq documentaries - two were nominated for Oscars yesterday - go beyond the death tallies to rekindle the sense of dread felt in the conflict's first days, writes Ed Pilkington.

There is a scene toward the end of the documentary The War Tapes in which a US soldier reads from the diary he kept of his year's tour of duty to Iraq in 2004. "Today is the first time I shook a man's hand," Sgt Steve Pink recites in a deadpan voice, "that wasn't attached to his arm." In another sequence, the soldier and his fellow National Guardsmen spend off-duty time discussing in earnest whether the feel of a severed limb most resembles that of a raw roast or sausage meat.

Almost four years into the Iraq war, and countless suicide bombings, ambushes, military raids and Bush speeches later, scenes such as these still have the power to mesmerise. Remarkably so, given the numbing effect of so much time, so many news articles, so much bloodshed.

When headlines such as "77 dead in Iraq bomb carnage" (December 31st) no longer generate outrage or any kind of reaction at all, a new approach is called for, one that can reopen emotional pathways long cauterised. In the last year, there has been a sudden ripple of powerful documentaries about Iraq, films that go beyond the death tallies and rekindle a sense of fear and horror as urgently as in the war's first days.

This year's Oscars longlist for documentaries included four about the Iraq war, and two - Iraq in Fragments and My Country, My Country - made yesterday's nominations. The moment undoubtedly belongs to the Iraq documentary, and one of the reasons is the timing. When Iraq was invaded in March 2003, a number of Western film-makers dusted off their lenses and headed for the country. Given the delay in filming, editing and then finding distribution, several of these films are reaching the big screen simultaneously.

James Longley, the American director of the Oscar-nominated Iraq in Fragments, thinks this coincidence has created a false impression. For him, the striking thing is not how many Iraq documentaries have been made, but how few. "When I first started filming in April 2003, you could count the number of independent film-makers in Iraq on one hand. To me, that was startling. Given that America had just occupied another country, and would do so for years, the attention it got from film-makers was minuscule."

The attention Longley enjoyed from sponsors was similarly minuscule: he was turned down for funding by several backers, and in the end decided to pay himself out of the royalties from his previous movie, the acclaimed intifada documentary, Gaza Strip. Of the four longlisted Iraq documentaries, Longley's Oscar-nominated Iraq in Fragments is the most obviously cinematic, which may well endear him to the Academy.

He breaks the narrative into three chapters. The first follows the fortunes of an 11-year-old boy from the Sunnis of Baghdad, chapter two tracks the religious fervour of the Mahdi army, loyal to Shia cleric Moqtada al-Sadr and the final section moves to the Kurdish north. What allows him to play with his images, and to have had unparalleled access to groups such as the militant Shia Mahdi army, are advances in technology since America's last major war.

At the time of Vietnam, most documentaries - the best-known is Peter Davis's Hearts and Minds - had to rely heavily on TV news footage. Longley, exploiting new lightweight, high-quality equipment, was able to spend more than two years in Iraq, doing all the shooting and sound himself.

American director Deborah Scranton makes the boldest use of technology, in The War Tapes. She gave cameras to 10 soldiers from a New Hampshire regiment on tour in Iraq, and the film draws on footage from three of them. In one extraordinary sequence, a full-scale gunbattle in Falluja is filmed from a camera strapped to a soldier's gun.The dramatic impact is overwhelming.

But the most powerful moments in these four documentaries come when the directors make use of the intimacy the new technology permits. Laura Poitras, director of Oscar-nominated My Country, My Country, spent eight months in Iraq in the run-up to the elections in January 2005.

Her film follows the fortunes of one man, a Sunni medic called Dr Riyadh, and his family as he stands for a council seat. As the film progresses, and his world crumbles around him, his face takes on an expression that is part bewilderment and part despair, as he has a premonition of the descent into hell that is to come.

Poitras manages to explore these issues of power and powerlessness with a subtlety that only cinema - as opposed to the immediacy of newsreel - can achieve. In one scene, Riyadh's wife is trying to swat a fly as gunfire breaks out, just outside the window. It's a succinct portrayal of violence that is terrifying in its ordinariness, and a metaphor for America's vain attempts to squash the insurrection.

This kind of film-making is not without risk. James Longley's film gives a harrowing account of Shia extremism after Saddam's removal. There is an awesome sequence of the Mahdi army rampaging through a market in Nasariyeh, attacking alcohol sellers in an attempt to "Islamicise" the city. Days earlier, a similar militant raid in Basra led to a bloodbath. "That's never comfortable," Longley says now, with considerable understatement.

During filming of a protest outside a mosque in Baghdad, Poitras was taken aside by a man who threatened to cut off her head. Only her relationship with her subject, Riyadh, saved her.

In turn, Riyadh took a huge risk in agreeing to be the subject of her film, as she was only too aware. More than 200 of his associates have been killed since the 2003 invasion.

Like Longley, Poitras brushes aside the question of her safety: "There is a sense of obligation. I needed to try and understand what my country was doing to the world, and communicate it."

Paradoxically, the most overtly polemical of the four longlisted films, and the most searing, is Patricia Foulkrod's The Ground Truth - paradoxical in the sense that Foulkrod has never been to Iraq. Her theme instead is the brutalising effect of the war on American soldiers. She began by interviewing injured soldiers in military hospitals, and soon realised that she needed to probe into deeper and darker territory.

"I had the same feeling over and over again, as I talked to these men, that they carried a terrible burden. And then I got up the courage to ask them about it - about killing. I saw it in their eyes: an inexplicable feeling of heartbreak and loss and loneliness."

The result is one of the most crushing critiques of the US military, and of armies in general, as glorified killing machines. Quietly, devastatingly, soldiers relate their experiences of wreaking death in Iraq. In one scene, a marine describes a day in which he saw many Iraqis lying dead and wounded. When asked by a senior officer why he looked so despondent, he explained what he had seen and said it had been a bad day. "No," replied the officer. "That's a good day."