It is tempting to tell oneself, "Yeah, but that's Bryan Fischer. Nobody even listens to him." I think we know better. But just in case this thought did run through your mind, here's former governor and Republican candidate for president Mike Huckabee on Fox "News" saying essentially the same thing.
You and I may agree in our opinions of Fox "News," but we also know that many people rely on it as their primary source of information about the world. While we might be able to dismiss Fischer, Huckabee has a huge audience. And there he is suggesting that school violence is the consequences of us removing official Christian prayers from our public schools. If it is not already obvious to you why this is problematic, I agree with everything Hemant Mehta (Friendly Atheist) said here.
If we want to blame ourselves, or at least acknowledge our own role in tragedies like this, we need not look toward school prayer. We have become so thoroughly desensitized to school shootings and similar crimes in the U.S. that we are unable to have intelligent discussions about how to reduce their occurrence. Our responsibility lies in our refusal to act.