Matthew O'Brien grew up in Oshkosh, Neb., population 762, and the self-proclaimed, "Goose Hunting Capital of Nebraska." The local hospital has exactly 10 beds. The newspaper publishes once a week. The nearest major airport is 220 miles away in Denver. "The middle of nowhere," says O'Brien, 22. Maybe that's why O'Brien enlisted in the Army in 2004 and became a paratrooper -- 82nd Airborne, 2nd Battalion of the 508th Parachute Infantry Regiment, Delta Company. He did a tour of duty in Iraq three years ago and was deployed to Afghanistan in February. Afghanistan is where he lost the vision in...