I have armed security personal in my workplace, so that doesn't bother me (to the poster before RvB).
RvB, those private sector companies/businesses that you named can and many have put armed guards/security in place. I have no problem knowing that if I go to a mall chances are they have armed security in the building, or off duty LEO's. At local hospital's in my area there are armed security officers in the building, doesn't bug me at all. Parks usually have beat cops that routinely are in the area. The only amusement parks I've been (6 Flags, Disney on both coasts) have armed security on hand.
In a school, the same people regulate the guards and training they need that regulate the rest of the school, local communities and states. The military type power already exists.
There are no shortcuts. No do-overs. What happened, happened. Trust me. I know. All of this matters.
Gentleman's League Record:
Season 1: 7-9 Missed Playoffs
Season 2: 18-1 Superbowl Champs