Nina Berman, whose work has appeared in National Geographic, Time and the New York Times, says "I've been a documentary photographer since 1987 working in a dozen countries including Afghanistan, Bosnia, India and Vietnam. But most of my time has been spent traveling the U.S.A. trying to understand the American Way of Life." Here are some of her photographs from the Purple Hearts project, a series of photographic portraits and interviews with American Marines and soldiers wounded in Iraq.