We live in a period in which memory of all kinds， including the sort of larger memory we call history， is being called into question. For history， as for the individual， forgetting can be just as convenient as remembering， and remembering what was once forgotten can be distinctly uncomfortable. As a rule， we tend to remember the awful things done to us and to forget the awful things we did. The Blitz is still remembered; the fire-bombing of Dresden， well， not so much， or not by us. To challenge an accepted version of history--what we've decided it's proper to remember--by dredging up things that society has decided are better forgotten， can cause cries of anguish and outrage. Remembrance Day， like Mother's Day， is a highly ritualized occasion; for instance， we are not supposed， on Mother's Day， to commemorate bad mothers， and even to acknowledge that such persons exist would be considered---on that date--to be in shoddy taste.