Absolutely, but the US have a gun culture that is in direct conflict with this sound proposal. Another measure would be to raise the punishment for being an ac

Absolutely, but the US have a gun culture that is in direct conflict with this sound proposal. Another measure would be to raise the punishment for being an accessory, according to https://www.sandyhookpromise.org/blog/gun-violence/16-facts-about-gun-violence-and-school-shootings/ https://www.sandyhookpromise.org/blog/gun-violence/16-facts-..., at least one other person had knowledge of the attacker’s plan in 80% of the cases. I don't think metal detectors or more surveillance at the school will help enough. But implement the first two measures as a start.