specifically in response to the mass shooter phenomenon. Mob mentality is definitely a thing. People will absolutely do things against their nature if others around them do it first. The new twist is how the information age plays into it. Maybe in decades past, if you were depressed and had some underlying violent or self-destructive thoughts, they just kinda simmered and never made it to the surface. But these days, you see and hear about all the people who feel the same as you, and when one does decide to lash out (at the world or themselves) it becomes very public information. At some level, you now know you aren't alone and it somehow feels more OK to feel the way you do. It also gives you the nudge to maybe act on your impulses. So it is at least somewhat true to say that every mass shooting and every suicide ever so slightly encourages the next one in a way that just wasn't true last century.