It seems like every few months there is a news item about a guy who takes up arms and kills as many people as he is able before being put down. Sometimes there are targets in mind, others the deaths are quite random. It’s sad news, but I doubt anyone who reads this is unaware.
Whenever the killers have a religious background, especially when it factors into the killer’s motivations, many atheists are sure to place part of the blame on the religion itself. I do too, but less directly than most.
The killers are mentally ill. We can argue that they aren’t all mentally ill, but it can’t be argued that this pool of killers are not, on average, more mentally ill than the general population. Their brain chemistry is rare and so puts their behavior at odds with cultural and societal norms. Their indoctrination didn’t do this to their brain chemistry. However, their indoctrination and the beliefs of those closest to them inform what they do about their problem.
There is a large stigma regarding mental illness in the United States which leads families and individuals to deny symptoms and shy away from treatment. Most religions don’t have a hard line against medical treatments, my ex-denomination excluded, they do put a lot of faith in spiritual sovereignty. If a benevolent God created us equal with freedom of will and thought, then a select few of us can’t be naturally deficient in will or thought. The mind, spirit or soul can’t be subject to variations of brain chemicals if any transcend the material world.
Mental illness should be at the forefront of our thoughts when these tragedies happen, but for the most part it’s not. I didn't want to post this immediately after such an event, I would feel like I'm capitalizing on a horrible thing, but it will happen again and we should do what we can to change this stigma and get these people help.
I have no affiliation to the Brain & Behavior Research Foundation, but believe they do good work in the field. If you have some time, look it over. If you have some money, donate.