I think this same group would object to "Saving Private Ryan" being shown, and I think in both instances, that is overkill.
But Saving Private Ryan was a staged recreation, and they COULD have made the movie without language, even if that would make it less "realistic".
On the other hand, this is from the reports actual words by actual people, what they really said in response to 9/11. I don't think we have to censor the truth, just put warnings on the show.
But I probably wouldn't have been upset with the Janet Jackson incident if there had been an appropriate warning and the V-chip setting for the show had been appropriate.