As I was thinking about the anniversary of the attack on the Twin Towers in New York on this day 11 years ago, I also thought about Hiroshima, which I visited in 2004.I avoid political commentary in this blog. So you should read nothing more into my post today beyond the fact that there have been many events in human history that have had profound impact on the architecture and psyche of a city but which also changed how everyone views the world. And I would say that 9/11 and the bombing of Hiroshima on August 6, 1945, are two such events.This photo, incidentally, shows the modern, arched Hiroshima Memorial (which shelters an eternal flame), framing a building which stood near ground zero. This building was left standing as the only remnant of a city center that was largely destroyed in the blink of an eye.