My daughter goes to a private school. As a parent, I volunteer my time there and so I'm fairly familiar with the physical layout of the school.
The front door of the school opens directly onto the administrative office. Someone opens that door, and steps inside.
That was the two women at the front desks. They're dead or dying. No one has called 911.
That was the large window that glasses in the director's office. He's dead or wounded.
That was anyone at the copier, or anyone coming in from the hallway.
Three steps into the hallway and one step to the right is a K/1 classroom. Six steps to the left is a 1/2 classroom.
Is someone scrambling for a phone?
Farther down the hall are two K/1 classrooms that face each other. There are two more classrooms past them.
A teacher or teacher's aide might be opening a door, looking out in the hall.
At the end of the hall, a left turn takes you out onto a fenced-off playground. There's an exit gate in the fence.
This could be a lunatic, a vengeful ex-spouse or ex-lover, a gang banger. And unless they choose to take hostages, it's all over in less than a minute.
If I'm there, I'm probably dead in the hallway or the office. And there's nothing I could do to change the outcome. Aside from response time issues, California is a "may issue" state; the city of Los Angeles defers to the county of Los Angeles, and both of them are "won't issue".
I'm glad I often tell my daughter that I love her.
So. I'm at the mercy of fate, just like everyone else.