In 1998, the Virginia-born Powers enlisted in the National Guard at the age of 17; five years later he re-enlisted, and the following year he was sent to Iraq as part of the US army's Explosive Ordinance Disposal unit. What he saw and lived through didn't, he maintains, make it directly onto the pages of The Yellow Birds ("The story isn't real," he said in one interview. "It isn't anything I experienced.") but inevitably, a great deal of detail has.
It has made him a finalist for the US's National Book Award and seen him shortlisted for the Guardian First Book Award, too. Excitement about him built from the moment his book went up for auction, and starred reviews have attended it since it first appeared. He's happy but cautious when I congratulate him on his success – he wrote for years when he was younger and tried to write a novel in high school, he admits, a little embarrassed, and this book's first draft didn't survive. It needed to be pared back, with a change of focus, before he felt it was ready.
Not so many writers go through what he did, however. It was a combination of the practical and the idealistic that made him enlist that second time. "My father and both my grandfathers served in the army," he explains. "Nobody even suggested I do it, but I felt an obligation to that tradition, and also college is very expensive in the US and I wanted to go there. The army would pay for it. I suppose I thought about the reality of war as much as I was capable of it at the time, but there was a degree of naivety."
The Yellow Birds tells the story of John, an American private in Iraq, and what happens to his close friend, Murph. It follows the unexpected raids, the effect of war on his superiors, the "body bombs", where a dead man's insides have been removed and filled with explosives to trap the soldiers. But it also follows John's experiences when his tour of duty is over and he has to come home. How hard was the experience of writing about his war, once Powers himself had come home?
"I guess for me it was cathartic - I felt I had to get to one level of acceptance of my experience, get enough distance to think about it with clarity, to be able to write about it. I had to deal with my own personal issues before I could write anything. There were definitely days that were challenging personally."
When he first came home he was constantly asked what it was like in Iraq and says he didn't know how to reply. Writing the novel was a way to do that, although he didn't want to write a memoir. "I needed the freedom imagination provides – but also to imagine myself into the lives of others."
There is a surprisingly strong imaginative element to his novel – when John leaves Iraq and is waiting in Germany for a flight home, he visits first a church, then a brothel. The sacred and the profane have long been linked together, but here they play a joint part in a man's recovery from violence and what Powers calls "the extremes of human experience".
They're testament to the artistry in his novel – his aim was to present the army experience as realistically as possible, as well as the country he was in, but he also wanted to question what happens to an individual when they experience war. I ask about Hemingway, and Powers says he's not sure he recognises that author's presence in his own work, but does admit to the influence of poets like Dylan Thomas and novelist Thomas Wolfe. Stephen Wright's Vietnam novel, Meditations In Green "opened things up for me.
I didn't model my book on it but it made me feel I didn't have to worry about fitting into anyone's conception of what a war book can be about".
Novelist Glenn Patterson once said that fellow creative writing students were envious of him coming from Northern Ireland as they felt, thanks to the Troubles, that he had something real to write about.
"So my friends had to die so I had a good subject for a book?" he asked. I suspect Powers would feel the same way about his own route to literary success. Pain and suffering are still pain and suffering, no matter what literary gold we can spin them into.