The Sultan writes an excellent article that explains all this.
The story of Islam is a murder mystery. It's not the kind of murder mystery where you wonder who did it, but when it will end. The detective peering with his magnifying glass at a scrap of fiber left behind on the carpet or a curly piece of hair caught in the door isn't really trying to sort out who did it. He knows who did it. The great mystery that consumes him is how to make the killer stop.
This isn't a story about right and wrong. Right and wrong aren't serious propositions in the arid deserts where the murderer comes from. Right is power. Wrong is not having power. A man is right because he has power. A woman is wrong because she doesn't. A Muslim is right because he has power. A Christian is wrong because he doesn't.
When a woman has power and a man doesn't, then the man has been dishonored. When a Christian has power and a Muslim doesn't, then the Muslim has been dishonored. There is only one answer for dishonor, death. Kill the one who has dishonored you so that you can feel powerful again. The men with the magnifying glasses will call it extremism, but it's much simpler and much more complicated than that.