This was certainly a tragic accident and of course it should never be forgotten.. in fact, my AP US History textbook last year from ca. 2003 or so already went up to the 9/11 attacks!
I was only 6 years old when it happened, and being in 1st grade (and elementary school), I had no idea what was going on.. that could have been different had I have been in middle or high school. It wasn't until I got home to watch the local news with my parents that evening to finding out what happened.
My condolences go out to those of you on PC with connections to people who died in such a tragic accident. We will certainly never forget this day.