Deceiving spirits exist. The spirit of deception is the initiator of wars. His greatest deception is that war is merely murder, and that murder is the ultimate ends of war. He makes war successful through lies, and deception - the deception that war is not murder, or if it is murder, justified murder in a quest for justice. He is behind the "just war" doctrine both in the secular and religious conceptions of "just war".
No war is just. War is of the anti-christ because it is of the father of lies, the devil. Once deception blinds the masses, the masses just aimlessly and vehemently murder each other, thinking they are justified.