Watching coverage of the crimes at both Penn State and a Colorado theater, it becomes apparent: There's stuff you're supposed to say, and stuff you're not supposed to say.
"Tragedy" is okay. "Mentally ill" is okay. "Evil", with a capital "E" - not so much.
This is because acknowledging evil is allowing that there exists something beyond our tangible, test-able world that wants to do us in... and that means our whole western edifice crumbles. And so, instead, we resort to the language of neurology or we talk purely about upbringing, or we change the subject to safer ground, talking about preferred go-to explanations, like weapons policy or parenting failures.
Having the fortitude, in a culture that fancies itself "rational", to acknowledge evil, is not easy. But you know what? It might be easier than the alternative, of trying to explain holocausts, mass-murders, planned starvations, sexual abuse of children... with a vocabulary stripped of the words to to acknowledge the presence of actual, spiritual evil. Denial may be natural, but that doesn't mean it's simple to pull off. It can take years, not to mention, say, thousands of professors, to help us get past our barbarian suspicions that something transcendent is afoot.
Even Christians are embarrassed by it. Some, of course, blame the devil for everything - that's one error - but others don't want to blame him for ANYTHING. We're embarrassed, I think, because we don't want to seem so...so... backward, so out-of-step with our modern, western culture. (Funny, isn't it? In almost all other parts of the world, people have no problem whatsoever acknowledging realms of spiritual evil. And the same westerners so intent on cultural openness will immediately reject the idea of spiritual evil as backward. Same thing happens in discussions of sexuality.)
But eliminating the vocabulary of evil, the reality of Evil, doesn't leave us in a more enlightened world. It does the opposite.
The Gospel is the only approach that truly is not simplistic, that looks at the messed up families, looks at messed up hearts, looks at messed up neighborhoods and says, "There's biological problems, there's sociological problems, there's psychological problems, there's moral problems, there's spiritual problems, there's demonological problems...we're going to look at all of those things, we're going to deal with all of them. All of them!" ... Until you embrace the Christian understanding of evil, you are reductionistic, you are simplistic. You'll either make the liberal mistake of underestimating cosmic evil, or the conservative mistake, frankly sometimes of just saying we can't do a thing.
Of course, there is a stream of the Christian religion, in the west, that happens to be embarrassed by any aspect of the Bible that contradicts our reigning culture, and - guess what? - decides that the culture pretty much has it right, actually. And there is another stream that embraces The Devil as all-explanatory, from why I caught a cold yesterday to why the sink got clogged when we were in a hurry.
As C.S. Lewis points on in The Screwtape Letters, both outlooks, themselves, may be suggestions of the Enemy. The Gospel, thank God, actually gives us the resources to call evil for what it is, and provide a context for it that keeps us from being frightened.
Bad news: Evil actually exists. Even if we modern westerners might try to ignore it.
Good news: God knows it. He does not escape it. He sees it. He does not detach Himself from it. And He tells us that not only CAN it be defeated, not only are we to play a part in that, it WILL be defeated. For now, we mourn with those who mourn, but joy comes in the morning.