I realize this is heresy ... but I think this is exactly the sort of training TSOs should be receiving.

As has been pointed out here innumerable times, TSOs are not law enforcement officers. They don't carry firearms, much less receive any officially sanctioned training on the use of firearms. Any action they take in order to try to stop a mass shooting is likely to be ineffective at best, and detrimental at worst. The last thing any of us need is an untrained hero wanna-be (TSO or passenger alike) charging into a situation and making it worse.

We train our children to react to imminent danger (a downed power line, an abandoned firearm, etc.) by backing away and calling a competent authority to the scene to deal with it. Heck, we train adults to do this. The same should apply here.