Here Gilles Peress captured a striking image of guerilla warfare the day following Bloody Sunday, the 1972 massacre of 13 unarmed civilians by British soldiers in Derry, Northern Ireland. An Irish Republican Army soldier, gun drawn, leaps over a wire fence, his face turned from the camera and further obscured by a balaclava. Anonymity here has a practical purpose: British authorities could more easily arrest the subject if the photograph showed his face. Peress took thousands of images over three decades as he documented the war for independence from British rule in Northern Ireland.