Predicting When Someone Will Snap

Wow-- the media again is providing non-stop coverage of two massive shootings in the developed world--Germany and Alabama that is.
I noticed a few news headlines mentioned that a potential plan is to work on "predicting which citizens are most likely to snap". Hmm interesting. Having worked in the Mental health field myself I have never seen anybody very good at predicting anything at all. That's the nature of mental illness--it is unpredictable. Sure we can sometimes stop and prevent suicides, but think of how many thousands of people commit suicide every day. Some times nobody had a clue and sometimes it happens during an actual "suicide watch".
I use that analogy as I feel there must be some aspect of depression in a mass shooting. Mixed in with incredible narcissism and anger.
Of course, I would like to see semi-automatic weapons banned. Unpopular choice. Then there is all the "target practice" young people get with violent video games. Another unpopular item to ban. I guess lastly the only way to prevent copy cat shootings, would be to simply ignore them int he media. Unlikely.