You overlook the possibility that pre-marital sex is forbidden in many cultures for practical reasons. The "modern western" view that the sex organs are a form of home entertainment system ignores the purpose they actually serve and is socially destructive. In this, I understand perfectly why the radical islamist feels the need to defend their society by attacking us.
I will not comment on killing innocent women and children, as I think it is a straw man and doesn't belong here, but I do not think that if we can only get a bunch of Arab men laid, that it will stop the fighting.
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