Shooting at a local school

at the schools in my area, once school has started you must check in at the main office before being allowed to go anywhere regardless of who you are. our high school has a security shack that is the only point of entry once the gates are closed and has several armed security guards and cops patrolling everyday. i live directly across the street from an elementary school and they lock all doors except the one in front of the office so that no one can get in without being seen.
i personally believe that every honest and good man in this country should have the right to shoot people like this. we hear about people killing the innocent everyday so why cant the innocent kill them once they prove their guilt by committing the act?
like charlie daniels said "take em out in the swamp take a short piece of rope, tie em to a stump and let the rattlers and the gators do the rest"
screw them saying their mentally ill and didnt know what they were doing and then live a comfy life in the mental health ward, or sit on death row for ten years. i guarantee anyone advocating that the death penalty is wrong would change their mind if their kid was in there today. i guarantee that i wouldn't hesitate to kill him had one of my little nephews or niece been in that school.