OVER THE WEEKEND, I read Tom Nagorski’s Miracles on the Water : The Heroic Survivors of a World War II U-Boat Attack, and enjoyed it very much. It’s the story of the sinking of the City of Benares, a liner carrying children being evacuated from the Blitz to Canada and the United States in 1940. One of the survivors said that he had never imagined that women and children were capable of such heroism. I shared no such preconceptions, but it’s still a terrific story.