The commercial called "Respect" was not banned, but withdrawn from use after being broadcast on SuperBowl 36. Anheuser-Busch produced the ad as a tribute, and felt that running it repeatedly would make it look like they were trying to capitalize on the tragedy.
Other people asked questions on similar topics, check out the answers they received:
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them