Nah, it's not so much the day itself that bothers me. It's the political bullshit that followed. If anyone has really tarnished the legacy of the dead, it's the politicians and corporations benefiting from the bloodshed of "The War on Terror".
Don't misunderstand me.
Oh, also the WTC was bombed in '93. Then there was the Atlantic Olympics bombing...the Oklahoma City bombing...yeah, 9/11 was bad, but we've been hit before and people forgot about the dead there.
Also people make fun of WW2 all the time. Last I checked, Pearl Harbor was far worse.