So why do you suppose no one was packing?
I do not konw. My guess is that if someone was packing, they sure didn't talk about it, for fear of hearing "why didn't you do anything?"
Or maybe it was just younger ppl that didn't think to have a gun. I know 2 vets (1 active, one retired?) were hit, and one died. I have to think if it wasn't Batman at midnight... but "Saving Private Ryan" at 4 pm, you would have a threater packed with older ppl, and plenty more fanny packs with Colt 45 in tow.
Very sad. Tough to second guess the situation.