Six joyful summers and six hopeful springs have passed since so many good people were slaughtered by Islamist radicals in 2001. When I think of the summer games played by the victims' children and the annual spring rituals of their widows and widowers, I take some satisfaction in our human capacity to take life by the hand and go forward.

But I also cannot forget the agony of that day and the profound pain we the living endured as we attended the funerals and comforted the survivors. Indeed, my anger, our anger, is not only a memory. It is a living, breathing, seething thing.