And while we're just hurling words around: This push into an analytic mindset comes from a part of the brain called the amygdala, which is responsible for emotions like anxiety and post-traumatic stress. This hunk of grey is what kicks the rest of the brain into gear when confronted with tragedy, causing people like the Sandy Hook truthers to start picking apart all the innocent inconsistencies in the story to form some kind of conclusion that isn't just "the world is a sea of cruel happenstance."
That's where anti-vaxxers come into play, as the rise in autism caused people to search for one clear-cut cause while muddling a 1999 decision by the FDA to cut down on mercury in vaccinations (which was done only as a blind precaution). You take those kinds of "better safe than sorry" measures, add some bullshit correlation between the rise in autism and the rise in people getting their kids vaccinated, and suddenly that fear center of the brain can lock onto a target.
It sounds like absolute brain damage to believe that the government is giving kids autism and covering it up, so naturally the next step is to harass and shame them as much as possible, right? Only that's kind of the problem.