Yeah, I'm not a police officer, so don't try asking me "what I would have done."
The job of police officers is to get in there and stop bad guys at risk to their own lives. I understand none of them want to die and they can't run in there blind but there are too many fat entitled union protected pieces of shit on that job if they know someone is in a building shooting kids and they don't posse up and get the fuck inside. Jesus, if ONE cop is there, he should be rounding up other adults to get in there and surround and take down the shooter. It's an AR, not a death ray. He can't shoot everyone if they are rushing him. Certainly not 19 grown ass adults.
You aren't getting paid $80k and a lifelong pension to be a fucking desk jockey, anyone can do that job. If police in this country aren't going to do hard jobs correctly then they don't need to be paid anything close to what other professionals are paid. Get the fuck off the job. You are getting paid disproportionate to your intelligence and skill level because you are supposed to have the adrenaline necessary to throw yourself into the line of fire to save vulnerable innocents. If you are sitting around for an hour waiting for overwhelming force to show up then this isn't the job for you and kindly fuck off.
I've often thought about my fight vs flight instinct and while I do think I'd probably flee if I had an opening, I think if I'm in a room with 30 other people and a gunman has us all there, I'm whispering to others, yo, as soon as this fuck looks away ten of us need to pounce him. It's way better than sitting there waiting for him to shoot you one at a time.