Right. I'm not implying 9mm isn't a lethal caliber it's just that I think it's harder to kill with one when used indiscrminantly than, say, a 7.62.
I also think that if backed up against a wall it would be easier to make a decision to rush the shooter who is holding two pistols than a AK. Psychologically.
9mm is good for killing europeans. For dangerous people, use a 45 ;)
Sheer speculation alert: If this was a couple of the lecture auditorium classrooms, they have steps down and the seats and tables are attached to the floor. If you come in from the back and start shooting, it would be extremely hard for anybody to get out of a chair, get to the end of the row of solid desk material, and run up the stair steps to knock you down. Think of a theater.
And if he did in some rooms tell the kids to line up at the FAR wall, and then started shooting at them, they might be too far away (20-30 feet) to be able to rush the distance and get him, especially if when he emptied the clip he stepped out into the hall.
Now, if that is the case someone could be on the other side of the door and get him, but who is going to do that? If you made it to the hall you are going to be running away, not running to where the gunshots are.
ALL SPECULATION. I’m waiting for the real news.