Remembrance is not a choice; it is a necessity. And that act on 9/11 should always be about the names and faces of those who vanished, about the truncated lives, these possibilities and dreams they never had the chance to realize. They did not have the good fortune to die one at a time. And that is why we must remember them one at a time. The more we focus on the small scale, the individuals, with all their frailties, the families broken, the men and women still in mourning, the rooms uninhabited, the closer we will be to making remembrance a moral act.

Jay Winter is Charles J. Stille Professor of History.