I have written a lot about the terrorist attacks of September 11, 2001 over the years, including a book on United Flight 93, which went down a few hours from my home in central Pennsylvania. In much of that work, I argued for the importance of that day not only in its human and material cost but also in what it represented as a contribution to the American civil religion. Core aspects of traditional American national identity—masculine heroism, a democratic citizenry prepared to stand in its defense, the deeply spiritual values that were present at the country's origin—were displayed that day. I believed our collective memory of the response to terror by our heroic co-citizens would be sustained in our culture and perhaps even point the way to a return to previous unity.