[Blue Jays]

Very good point, henkster.
It is a scenario that I have often contemplated.
People are eager to post "Pull your own handgun and start blasting!"

The obvious question is blasting at...WHAT?
That random person seen coming down the hallway with a pistol in his/her hand might be another lawfully-armed person.
The optimal situation to me would be to lock a door, barricade it, draw my own weapon inside, and await the all-clear.

[Blue Jays]

You are correct about the "cowboy" immediate response, BigDaddy45.
My response would be to RUN and keep the darn defensive firearm CONCEALED for as long as practical.

Uniformed officers do not need 100 people in OSU sweatshirts all simultaneously drawing firearms to "help" them find the shooter.
A genuine good guy will not get a hero's welcome while tensions are high.