B/c WWII is over and we already won that war. The war that we got in from 9/11 is still being fought and just like they did remember pearl harbor during WWII we can not forget that we are at war and will be until the enemy or us are totally destroyed.

Another note is that pearl harbor was mostly military and was a military target while 9/11 was a civilian target that was attacked not for military domination but for the sake of an idea.

I remember WWII on D-day and not on Pearl harbor but that is just me.