Originally Posted by
judolphin
Correct, but IIRC the TSA doesn't really require ID for anyone over 18 either

Just means you'll go through a little more trouble if you lose your wallet or something.
I flew MDW-BWI last month. I forgot my driver's license and TSA wasn't going to let me fly unless I could produce at least 2 items with my name (like credit cards, of which I had about 10) and something with my photo on it. Fortunately, my Costco Amex card has a photo on the back, and it is the only thing in my wallet that qualified.
Not sure if that's correct TSA procedure, but that's what they were enforcing.
It just occurred to me that I could pull up my Facebook page with my name and photo if needed, but I guess that's not secure enough for their purposes.