The thesis that I would like to introduce in this text is that Clausewitz’s magnum opus On War is a text full of thoughts and observations that are of great value for psychoanalysis in theory and practice. In order to properly make use of them, it is necessary to do the work of making a mental translation of his thoughts to the object of individual and interpersonal mental life. The present text claims to offer, by setting a metaphorical relation between war and interpersonal mental life, a mental bridge through which this translation can succeed. Freud, who is known for his frequent use of metaphors, actually often used the metaphor of battle and thus already brought war into association with psychoanalytic thought. The presented metaphorical relation will allow to include Freud’s metaphorical use of battle and, so I hope, to bring his thought into a relation with Clausewitz’s thinking. In order to provide such metaphorical connection of war and interpersonal mental life, it is necessary to understand Clausewitz’s general understanding of the nature of war.