After Iraq, US bomb disarmer searches for peace
Brian Castner served two tours as the commander of a US Air Force explosive ordnance disposal unit in Iraq.
In his memoir The Long Walk, he describes the "nerve-racking yet strangely exhilarating" work of disarming bombs.
A bomb technician can rely on robots, but often must use his hands. He is alone: The squad can't help him; they can only hold their breath.
The Long Walk describes the other long and solitary walk that took him back home to Buffalo in the US state of New York.
"The first thing you should know about me is that I'm crazy," he writes in the book's first sentence.
In an interview with the BBC in his house in Buffalo, Mr Castner says the noise of a diesel school bus carries him back to a humvee in the desert.
Even back from the war, he fears he will never be truly safe again.
Produced by Anna Bressanin, Camera by Chris Eadicicco