I don't think I'm going too far out on a limb in observing that this is quickly veering from the merely stupid to a pretty ugly kind of victim-blaming.
Mass shootings sometimes end when the killer has to reload his weapon and some alert bystander or victim tackles him. But the big issue with going into a school with a military style assault weapon is that it tends to take brute physical strength out of the equation.
We all know that, on average, men are larger and stronger than women. Most of us don't think women are helpless and passive and need men to protect them in a school.
But there's something else going on here besides just people staying stupid things about arming school teachers or drilling unarmed people to rush armed psychotics. It's not just an arms race of stupid. It's just an arms race.
Don't like that crazy people are coming into school with assault rifles? Well, get the teachers armed. (What could go wrong?) Can't handle armed assaults with predominantly female staff? Bring in more men! Most of us are trying to operate in a society where overwhelming physical force and firepower aren't the organizing principle. That can't be entirely the case. So we have police. We lock our doors. A lot of people keep their own firearms, at least in their homes. We have prisons.
But you've got some people -- either seriously or half in jest -- pushing for a use of force race to the bottom, where the violent, criminal, militarized zone is invading the civic space, even the school space. And this isn't New York in the 1970s or LA in the Crack War 1980s. Violent crime is still holding at levels we hadn't seen in the US since the 1950s and 1960s.
There's a pattern here that goes beyond just ridiculous ideas. There's a logic to it. But not a good one.