It's the same argument with serial killer movies (at the risk of showing my age there was a strong controversy with "Natural Born Killers" at the time): you don't kill people because you chatted on the internet or watched a movie.
You kill people because you had it in you. The things you were exposed before might color your act but that's it.
Hollywood is infamous for misunderstanding psychology. At best, Hollywood has outdated notions of psychology (favoring long outdated ideas like Freud, because such ideas are exciting). Hollywood sells movies, not understanding.
What we're discovering today is that there's a "pathway to radicalization". People are NOT born radical, they realign themselves as radical over time.
We who? This was known at least as far back as since Scientology and Holocaust.
There is this pervasive idea lately a crazy youtube video or text can't actually be harmful, which just isn't true. Ideas can inspire wars, murder, revolution, they can warp minds. People previously productive can end up obsessed with crazy junk. It is important to protect each other and ourselves from bad ideas. The question is how, of course. Some people violently oppose any form of curation, whether it be censorship by government, or choices made by companies like facebook. Others insist the solution to bad speech is good speech, but I've been seeing that fail on the internet for 30 years. Perhaps higher quality education can help, perhaps improving economic inequity can help. Other ideas are welcome!
Pure information is harmless, beliefs are not. Crazy beliefs emerge from the lack of critical thinking, not from the "dangerous information".
Therefore censorship is only good as part of "divide and conquer" strategy.
In the rare case that you're positive for a trait, you can be incited to it by stimuli.
For example, if you have an anger-management problem, you can live quite peacefully, left alone, but you are uniquely dangerous to provoke. Behaviors and stimuli that are harmless to other people cause a violent outburst from you. Same thing with alcoholics and, for example, pedophiles - stimuli that provoke no negative behavior from other people will provoke it in someone positive for a trait. Violent media left us with a tiny driblet of actual killers because only a tiny fraction of people are positive for a trait of being stone-cold killers.
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So what are we afraid of? We have barely any actual killers. We're afraid of enablers.
We have a tiny, tiny group of people that will dare to do crimes (say, shooting up a synagogue) when there are clear and present consequences for it. I'm quite sure, however, we have a still small, but much, much larger group that are "latent" trait-positive for violence. They'd do it - if they could get away with it.
What we're really scared of is a third group - which might be a group so large that it could be anywhere from 30-60% of our society. People who could be coerced into not caring about the violence. That third group is the people who are trait-positive for gullibility (and several other related traits). I think it could very well be "most people" - a plurality if not a majority.
These are what enable horrible things. People who have bought into propaganda really don't do anything, and that's exactly what's so horrible about them; because they don't express some sort of obvious, negative externality in their neighbors and coworker's lives, nobody really cares if they believe horrible things. Because they don't really "act on" those beliefs - they don't go out and do things that hurt people.
But they also don't intervene when a crime aligning with their beliefs is perpetrated.
And that's what's so scary.
When a black man would get lynched in the old south, the real thing that made it possible was the hundreds of other bystanders who felt like the black guy deserved it. If they didn't exist, such a killer would rapidly be brought to justice. But instead, since so many were okay with it (and even cheered it on), not only would the killer get away with the act, but quite a few much more "minor" trait-positive people participated in it - people much less naturally driven to kill, but who could work up the courage to do so if they could get away with it.
The fact that there are so many Americans who accept this is enough to make me rethink my participation in society here. Who are we if we've become enablers of this? I can't fight this, there's no "there" there.