>>KenCoc+(OP)
Within a couple years this exact scenario will play out. A gunmen will talk in a crowded place loaded to the gills. Assault rifles, bullet proof vest, explosives hid around the building. He will pull out his gun and kill the poor unsuspecting first soul. After that initial shot someone with a concealed weapons permit is going to blow his brains out cutting his rampage short ( I truly hope the person who plays the hero is a little old lady packing heat in her purse).
>>grkbal+M2
Note that these things are pre-meditated and that the people doing this are clever enough to hit soft targets.
Little old ladies with guns are typically not present in grade schools, nor would you want them to be because their weapons could be taken away from them and used against others.