A discussion.
Human nature is the problem. Not religion. I think it's incredibly naive (whilst being an atheist myself) to say that religion is the source of a lot of violence. In my eyes it's an expression of something else that's wrong with humanity, or anyone who goes so far as to commit violence. I can't deny religion is a tool, because religion is one of many tools. It's just there're going to be a combination of other factors much greater than just religion that contribute to violence.
Look up the Stanford Prison Experiment, or Milgram and you begin to see horrible deeds and violence can easily be done without it...it's a matter of producing an us and them mentality, leading them slowly step by step and having them obey anyone who has some form of unquestioned social power.
Ouch, that's a bit one sided, but interesting.
Ibsen's great, a very interesting playwright, certainly innovative for the time. Very challenging for the 19th century too.