Tania Head’s story, as shared over the years with reporters, students, friends and hundreds of visitors to ground zero, was a remarkable account of both life and death. She had, she said, survived the terror attack on the World Trade Center despite having been badly burned when the plane crashed into the upper floors of the south tower. Crawling through the chaos and carnage on the 78th floor that morning, she said, she encountered a dying man who handed her his inscribed wedding ring, which she later returned to his widow. Her own life was saved, she said, by a...