You really do not need skills in that situation, and you, singular, do not need to win that fight. You need training like what society pays professionals for. In that position your job is to get in the fight, and pin your target down. That is, force him to stop shooting at children and take cover. Hopefully the rest of your team is maneuvering for the kill. Even if 'you' get pinned instead, that is still time that you have robbed from the shooter and delivered to your team --and others like children who need to run away.
Successfully confronting the shooter in this situation would not be all that difficult.
He's shooting and you're not. That means you can easily locate him, but he doesn't know you're coming. Tracking him down and cherry-picking your shot would not be that hard.
Yes, there's a possibility that he might pop out of a classroom while you're halfway down a hallway. If you're on your toes with the correct mindset, he's the one that gets surprised - not you. You still have a distinct and overwhelming advantage, if you don't lose your head. Remember, your adversary is a 17 year old kid, not a seasoned professional.
This is "Active Shooter 101" stuff. Anyone who's even read about the subject should know this. Any LEO certainly should. You don't rush in blindly, you quietly but quickly stalk your prey (the shooter).
Pawpaw and Textension are correct. This is not a pistol vs. rifle toe-to-toe fight. Nobody is expecting Peterson, or anyone else, to charge the Bolivia army with Butch and Sundance. I have never been remotely in this type of situation but I was a teacher for many years and thought of this situation many times. The officer only had to find the shooter, engage, upset his OODA, and neutralize the threat or at least buy time until the Calvary comes or the kids can get away. Move to the threat but do so in a way that you can be effective. Blinding rushing in may do nothing more than get yourself killed and now you have squandered away the opportunity to deter or neutralize the bad guy.
We are arguing the pistol vs. rifle yet we expect our teachers to turn away an attacker with books and staples, or a fire extinguisher if they are so lucky to have one in their room. No, not all teachers should be armed. Not all are cut out for it. Let the ones that are willing and able have the tools to protect their kids. The teacher's first responsibility is to take care of the students in their immediate care, not search and destroy. If the opportunity arises to engage outside the classroom or hold down the hallway then that is a bonus. Staff that is more mobile, principals, custodian's, office staff, may have more opportunity to S&D but even then it has to be carefully calculated.
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