This is probably going to be a very unpopular answer, and I don't mean to sound cold, but no, it doesn't. It was a sad event yes. It should be remembered, certainly, but that doesn't mean we should dwell upon it as though it was the worst thing that ever happened in history. The world has been filled with violence and tragedy since the beginning of time. As humanity, we can constantly pine away about the misery of the world, but the world has also been immensely awe inspiring and beautiful despite humanities tendency towards violence and hatred.
I choose to focus on the positive and to only dwell upon the negative long enough for it to serve as a reminder to be a light in the world. We can't stop tragedies from happening - all we can do is the best we are capable of. It does no good to continually dwell on one event in history. There's a time for moving on. Unfortunately, we have a government and media that like to continue to exploit the bad memories of that day for their own gain.