Why many persons are incapable to say the year of the events of September 11th ?

Answer 1

I think it's because of some degree of post-traumatic stress. I mean the Media played that scene, of the towers falling, *over and over* again and really *rubbed our noses in it*, in all the death and chaos and destruction.

And it's been proven that post-traumatic stress can and does screw with your memory, courtesy of excess cortisol on the brain, among other things

But don't just take my word for it:

Answer 2

Kuz they're gay.