I'd have two words for him: "Hurricane Katrina." Or go with the LA riots several years ago. The weapon you describe would be the best for the kind of rioting that ensued from the "entitlement class." Looting, raping, pillaging WAS occuring and will so again. Maybe in your town! There IS a place for citizens to have AR-15's that has NOTHING to do with hunting or even directly with the Secon A.