This year there are 83,267,556 Americans who were age 6 or younger on 9/11/2001, and the vast majority had not formed their first permanent memories yet. That's fully 27% of Americans who do not have (and can't possibly have) memories of 9/11/2001. (and 18.5% – over 57 million – were not even born yet…)
The oldest members of this cohort of Americans with no memory of 9/11 are College Sophomores this year.
These Americans cannot "Never Forget" because They Can't Possibly Remember It In The First Place.
"Never Forget" is swiftly moving into the history books (and should take it's rightful place) alongside "A Day That Will Live In Infamy", "Remember The Alamo" and "Give Me Liberty or Give Me Death".
On second thought, maybe we should start using that last one again.