If russian citizens take part in a war that didn't mean that Russia should fight against them. It's a crazy cause for war. Russian citizens take part in a war in Donbass, so Russia should fight against DNR? LOL. Or you think that terrorists from Beslan went to ISIS? I thought that they are in the prison or in the ground. Or you think that these guys come to Russia and will make a new terror act? They will do it, becouse Russia start to fight, and they will take vengeance on Russia. And smarter not to take part in this crazy bloody circus. So, if Russia fight against ISIS should Russia fight against DNR too? I dont't think so.