I think that members of a cult are partly responsible for some evil they do. Like I don’t care if you’ve been raised to believe that Warren Jeffs is a prophet, if you marry your prepubescent daughter to him you did that. And you bear some responsibility for not walking away beforehand (and frankly that’s more intense than condervativism because they will actively try to ruin your life over it). I think the people holding guns at Jonestown bore some responsibility too. David Miscavage isn’t some innocent duped by L Ron Hubbard, he chose to stick with Scientology and then act on it in evil ways. And as an adult he could’ve made a better decision.
Some victims bear no responsibility, but once you move to doing fucked up shit to others over it you do bear some responsibility. Because you could’ve walked away at any point and while it requires a lot of strength to do it, when it comes to choosing between being strong and hurting others we have a responsibility.
When you do a mass shooting after partaking in your own radicalization you are partly responsible for it.