The Law of War course deals with two issues: (1) the lawfulness of the initiation of hostilities by nations, and (2) the lawfulness of the methods employed in the use of armed force. The first issue includes situations in which one nation initiates the use of armed force against another, and the role of self-defense as a justification. It also includes the role of the United Nations in implementing use of force in a collective fashion when there is a breach of the international peace. The second issue includes types of weaponry that are prohibited from use, and obligations towards civilians and to detained combatants. On both issues, the course covers relevant international rules as expressed in customary law and in treaties. It covers international institutions that apply the law of war.