I respectfully disagree.
The weapon is your mind, and your willingness to act, not the firearm.
What good are unarmed guards against a BG with a gun? They can slow him down, they can allow more people to escape, if they are good or lucky (or both) they can stop him. How many things are handy to beat the BG to death with?
I am constantly told by LEO's and their bumper stickers that they are the "Thin Blue Line" standing between us and the bad guys. It sucks that these sworn law enforcement officers are unarmed due to political reasons. As a Soldier that has had some truly messed up ROE's in my day I sympathize. But that does not relieve these officers of their duty, nor release them from their oath.
It's a crappy situation all around, and given a choice I'd much rather have a weapon, hell a rifle and a fire team, to face an active shooter. But some times that doesn't happen.
Sometimes in life you pull the short straw. If that happens, you do your best to kill the other guy, and failing that die like a viking.
If they are unwilling to do that perhaps they should seek a profession that doesn't involve being one of the men on the wall.....