COLFAX, LOUISIANA — Early one evening, I went out for a run. I took a route out by Lake Iatt, passing through acre after acre of logged land, trailer homes and lush green farms. It was an easy out and back, but as I rounded the last corner, I was alarmed by clouds of black smoke that were blowing my way. Explosions crackled in the distance. The sounds put me back in Iraq, where I’d spent a bunch of tours as a photographer, listening to gun battles being fought in nearby towns or neighborhoods.