Security in school

I only heard that the student carried a gun and fired in the school in United States but none in my living city. I would agree with using metal detector if there had a situation. It is personal safety and I think nobody would say no if it really happened. Maybe people would say how about my privacy? Well, facing that I could only respond them life is precious. If anybody get hurt or killed with a gun in school, it will be a big problem and causes much more than private stuff. Everyone should care more about the others but not myself.