In some ways you've gotta love how any (and every?) sensible idea is taken to extremes, and how unless it can be perfect at those extremes, its not acceptable.
The idea that removing the legal barriers to allow teachers to have their own personal firearms with them, in school, so that, if they choose, they have something other than empty hands to fight back with becomes "arming teachers".
The did the same thing with pilots, after 9/11. It wasn't good enough that the pilot, in whose hands hundreds of lives were placed, daily, could be trusted to use their own judgement. Oh no, not good enough. What was "good enough?" to satisfy the objectors??
Allowing those pilots, who chose to, to attend a multi-day (two weeks???) training course, located in one place in the country (and remote from nearly everyone who would be taking it), requiring taking time off from work, paying for the training, and living expenses while training, all out of the pilot's personal pocket, only that came close to satisfying those who objected. And even that wasn't enough, in addition to that, rules were put in place requiring the loaded gun to be stored in a fixture that (as another poster pointed out) used a cable lock through the trigger guard, AND required the gun to be taken out, checked and put back in the box over an over during the course of daily flight operations.
If you set out to create a storage system deliberately designed to be dangerous and to discourage anyone from actually taking the only approved training course, it would be a challenge to surpass what we actually wound up with.
TRAINING is a word much in use now, so many people are scared of the idea of a gun (anywhere) unless the owner has training. But no one seems to know what training is acceptable. And, they are also falling for the lie that training makes everyone safe, accurate, and effective, and 100% of the time.
It does not.
You want training, so an armed teacher (or any individual) can shoot the bad guy, and only the bad guy. A noble goal. Now, wake up, get some coffee, and look at the real world.
Cops, who, arguably are the best trained people most likely to be met, and who are actually required to practice once in a while, miss the bad guy, and do hit innocent bystanders, all too often. (and yes, even once it too often, but again, its not a perfect world. If it were, the issue wouldn't even exist)
I'm not against training, Every one of us has had to learn how to use literally, every single thing in our lives. What I'm against is some third party standard, requiring XX hours of training, (and often only from approved suppliers, verified by some piece of paper) combined with the bedrock belief that without that, you are incompetent with a firearm.
And, because you are assumed incompetent, you are a constant danger to everyone one around. That's why they don't want teacher's able to be armed. They assess the risk of harm from an accident (due to the incompetence of the teacher) to be greater than the risk of harm from an actual attack. They aren't wrong to be concerned, there are careless people, but I think they take that concern to foolish extremes, and put everyone in that category, unless they have proof of (acceptable) training, or a badge and a uniform.
The real world shows us that while proper training increases the odds of success, it does not guarantee success, just as little or no training does not guarantee failure.
My point in this case is that, even if teachers and staff are allowed to carry, with approved training, the objectors will do everything in their power to see to it that the only approved training is as difficult and costly as they can manage, to discourage as many as possible from taking it. And it will be done under the claim of "safety".
Personally, I think the uncertainty of not knowing if someone at the school is armed would be a greater deterrent than a sign stating there are no guns on the premises. Of course, some are not deterred by anything....
People are being sold a bill of goods, under the false promise of safety. In quite a few different ways. One of them is that we can somehow stop these wackjob spree killers before they become wackjob spree killers.
There is a slim chance that the ones who make public threats can be stopped (or more likely, just delayed), but remember that there are legal standards for what constitutes a credible criminal threat. And, if their social media rantings don't meet that standard, there is no legal action that the police can take.
When the killer doesn't break any laws, until they start shooting people, there is nothing legal to stop them with. Period.