The Islamic campaigns did not target civilians at all.. the conquered became conquerers themselves which which the Islamic world expanded so quickly..i.e. the masses looked forward to the muslim arabs to come and liberate them from the wretched situations.

I am not talking about the need to fight the japanese or the nazis but the mass killing of civilians by both sides including the americans

yes there are many acts of mass murder that omitted from the past including the Crusder wars and the spanish inquisition etc...