I, too did the JROTC high school shooting thing. Sure we had guns at school, but this was late 70’s and at that time guns were for war, hunting, or shooting maybe one person that you really disliked. We had yet to have to come to terms with the idea of a spree. Might have happened by then, but we didn’t really think about it.
Technology and culture changes, and we have to adapt our responses going forward, hopefully not instigating a literal arms race in the process.