It appears that the Las Vegas mass murderer had no religion. Is it permissible to talk about the role religion plays in curbing anti-social behavior? If you believe in God, and that God knows not only what you do but why you do it, and that God will mete out punishment to transgressors of God's law in the end, aren't you less likely to transgress? I'm not saying that all or even most atheists are violent by nature; nor am I saying that all or most theists are nonviolent. Goodness knows there have been plenty of theistic murderers. What I'm saying is that for some people, religion is a deterrent to crime. Isn't it plausible, therefore, that as religion declines, mass murder will become more common? Just asking.
Addendum: I'm well aware that some religious adherents believe that killing is required (or at least permitted) by their God. I'm not talking about these people. I'm talking about people who believe (1) that God exists, (2) that God condemns murder, and (3) that God will punish murderers. Isn't someone with this set of beliefs less likely to commit murder? If so, then isn't it in society's interest to inculcate such beliefs?
