There is the mythology of the Green Berets, of their clandestine, special operations as celebrated in story and song. And then there is the reality of one soldier's experience, the day-to-day loss and drudgery of a Green Beret such as H. Lee Barnes, whose story conveys the daily grind and quiet desperation behind polished-for-public-consumption accounts of military heroics. In When We Walked Above the Clouds, Barnes tells what it was like...