Aggression

Abstract

Abstract This chapter discusses the concept of aggression. Article 39, the opening clause of the United Nations Charter’s collective security system, contains the term ‘act of aggression’, the existence of which in a given case falls to be determined by the United Nations (UN) Security Council. Recalling Article 39, the UN General Assembly, in 1974, adopted a resolution on the Definition of Aggression (Resolution 3314 (XXIX)). As the term ‘act of aggression’ is used alongside the terms ‘threat to peace’ and ‘breach of the peace’ in Article 39, the UN Security Council is not bound to determine the existence of an act of aggression to activate the Charter's collective security system and authorize the use of force by one or more States in order to maintain or restore international peace and security. In the view of the International Court of Justice and the International Law Commission, the prohibition of aggression forms part of customary international law. Here again, however, the distinct legal significance of the concept compared to ‘use of force’ and ‘armed attack’ is of quite limited reach. Contrariwise, the concept of aggression has been of considerable importance in the realm of international criminal law since the latter’s inception.