If I am in a mall that someone decides to start shooting up. I sure as shit am not relying on the armed security guard, who is likely an ex-high school football player who failed out of junior college, to help. I hope that there is one of those blasted "gun nuts" there with a conceal carry.
Why don't you just get a concealed carry permit yourself and remain armed while out in public? Do you have the mental capacity to act quickly when witnessing potential danger, take out your firearm in time, accurately aim it at the threat and pull the trigger in time before anyone is else harmed?