The tragedy in Newtown, CT, could have been avoided if there had been an armed guard at the school, or if any of the administrators had been armed. The suspect broke through the elaborate security system at the school, so that didn't work. Since this was a "gun free zone" the suspect knew he would not be opposed by anyone with a gun. The janitor saw him break in and immediately started to alert the classrooms. When the suspect entered the office, they turned on the PA system so the classrooms would be alerted. How did they plan on protecting the children and themselves from a mentally deranged madman who could just as easily have been armed with a knife or other weapon?
The tragic truth is that if any one of the teachers, the principal, or any of the administrators been armed, the incident would have been stopped before it got started. You can only fight lethal force with lethal force. As the NRA has pointed out, the best defense against a bad buy with a gun is a good guy with a gun. More gun laws, assault weapons bans, bans on magazine capacity, will only infringe on the rights of law abiding citizens. The criminals have never obeyed the gun laws on the books and never will. The thousands of gun laws we have now are routinely ignored by criminals who will use any means to achieve their objective.
And a question for Bloomberg and others who run around with armed body guards. Why do you think you have the right to defend yourself with a gun and the rest of us don't?