Disturbing new photos have emerged of the violence committed by U.S. troops against prisoners at the Abu Ghraib prison in Iraq, and some of the most shocking images don’t have a single human being in the frame. Instead, spattered blood serves as a metaphor for the horrors we have yet to hear about. “Comparing blood to paint, violence to art, is dangerous, even repellent. But in one sense, the blood on this floor is exactly like the paint drippings of Jackson Pollock, who captured the visible traces of action, the visual memory of gestures.”