(Several teenage patrons are reading the ‘What does your birthday mean?’ keychains.)

Teenager #1: “Mine’s September 11th. Wasn’t that, like, a bad day in history or something?”

Me: “How old are you guys?”

All Teens: “Thirteen!”

(I do quick mental math. I realize they were only six when the twin towers fell.)

Me: “Yes. It was a very bad day. Members of an extremist group hijacked some planes and–”

(While reading a keychain from the day the Berlin Wall fell, the second teenager interrupts me.)

Teenager #2: “Hey! What does ‘co-MUNE-ism’ mean?”