Well, I wouldnt let 9/11 instill fear in someone to fly. I would think that even the terrorist planners look at it like "Well, we did that trick, they are well aware of it, what are they NOT protecting". A genuine phobia to fly is different though. I have a phobia about burning to death. I think if I were caught in a burning building, I may well panic. But, as the situation hasnt presented itself, I may never know. And, although you can take Valium, or other meds, to fly, I would suspect one taking drugs to relax in a burning building would most likely be found in the rubble & aftermath.
I am flying in April, and look forward to it. I like the anonyminity of an airport. Flying is kind of boring; bring a book and/or MP3. And, enjoy it!