The bottom line question for control advocates needs to remain.
"who was he?"
"how was the firearm acquired?"
"would other means have prevented today's incident?"
The fact that an armed guard dispatched the shooter is good. However, it can't be recognized as the bottom line and end all of safety. It's one layer, that was successful in this incident, but just because there were no other fatalities, doesn't end it there. Two people were injured and that might have been managed through other means, maybe prior to the shooter getting a gun to the school.
In aviation we deal with massive layer, upon layer of safety. Most safety protocols come from someone else dying or getting injured. The result is the safest aviation system in the world. Gun control needs to be approached in the same manner.
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