I think it's absolutely correct to say that Nessa is a deluded, self-righteous fanatic, but it seems like the series understands that. I like that we're being given a heroine who is so deeply flawed, but not in the dark, hateful way that antiheroes typically are on TV. In a way, I'd say she's like someone from a Greek tragedy, with her well-meaning intentions leading everyone further down the path to hell.