When they fire from a mosque the mosque loses it's status as a non target under the rules of the Geneva convention.
Based on what I've read...its a automatic rule. Just takes one shot to change the status of a mosque to a target. They may pump everyone up with video display of Americans shooting at the Mosque...but its a simple rule with a simple result. I'm of the same belief for US facilities as well. Any fool that wants to hide behind their religion and use weapons offensively...gets what they deserve.