"If you stick your arm into a tigers cage, don't be surprised if he bites it off, he knows no better, but you do."

Unfortunately, in this case the tiger, having been made mad by those who controlled and brainwashed it, bit off heads, not arms - heads of innocent people who weren't even there when the arm was stuck into its cage.

I could understand it if they had attacked and beheaded Pastor Jones (understood, but not condoned). But I cannot fathom what was in their heads when they attacked and beheaded completely innocent people just because those people were different from them and, unlike Pastor Jones, were available.