How Hard is it to Stop Mass Murder?

And stop putting up "gun free zone" signs...just an invitation to wantabee mass shooters that they have no resistant targets.

Lt Col Charlie Brown - Legally anyone may carry a concealed weapon (thus the Liberal argument against it) even in areas with gun-free zones. A legally concealed weapon where no one knows you have it. If they find you have it they can refuse to do business with you. I know of Gun shops inside malls, plazas and squares. If the person legally uses it against a person attacker, mass-shooter or thug-attacker, then he is protected by law.
I would recommend he get a lawyer. Why be armed weapon-wise & unarmed legal-wise.