Only SFS folks and LEOs can carry on bases. They don't want anyone else in the mix if anything goes down - Security folks will follow war-time conventions in taking out anyone who isn't them, that shows a weapon.
Active Shooter instructions are a hoot - try to hide (but you aren't allowed to move out of your building because they call for a complete lockdown. If the shooter finds you, they tell you to throw things at him. I guess they feel that giving you a stapler against a shooter is a fair trade for insuring that only they and the bad guys have weapons.
You ain't lying. Just imagine if the Ft Hood troops were allowed to carry. Hasan would have been martyred instead of the bogus show trial. Most bad guys by now have an idea about the active shooter response and would just pick a large building and slaughter everyone inside.
I think everyone ignores the carrying on base rules. They do random vehicle checks but I have never seen them patting down anyone and that is where most would have their weapons.