Wow, you libs really have a problem distinguishing the difference between armed criminals and honest law abiding family folks that just want to retain the right to protect their families.
Infecting an assailant with Ebola cannot stop them from harming you. Did you really think about that question before you asked it?
You can not propose that certain Americans are qualified as a justification for inviting all Americans to the party. You are ignoring the risk of the constant presence of guns in the school environment. That is, your evaluation is limited to the duration of some horrible event, while the proposed policy affects EVERY day throughout the school year.
Do you not see that every day throughout the school year is already affected? Any time anyone wants to bring in a gun and start shooting, there is nothing to stop them NOW. That person is going to ignore the laws against murder, the laws against illegally carrying and/or owning a gun, the school policies on gun control, and any signs hanging up. You can either allow capable people to defend themselves, or maintain the status quo of a gunman having an unopposed free for all until the police arrive. Gun safety is not a difficult thing. A gun is not going to leap out of it's holster and start going off. With the proper training and a well designed retention system a gun is as safe as a pencil.