aggression

In biology, behavior used to intimidate or injure another organism (of the same or of a different species), usually for the purposes of gaining a territory, a mate, or food. Aggression often involves an escalating series of threats aimed at intimidating an opponent without having to engage in potentially dangerous physical contact. Aggressive signals include roaring by wapiti (American elk), snarling by dogs, the fluffing up of feathers by birds, and the raising of fins by some species of fish.

Aggressive signals allow the individual to assess the strength of an opponent and so decide whether to risk a fight. Many species use specialized structures during aggression, such as antlers in deer, or display plumage such as crests in birds. Most interactions end with one individual submitting or withdrawing before physical battle occurs: ‘fights to the death’ are rare in nature.

aggression

In politics, an unprovoked attack often involving an escalating series of threats aimed at intimidating an opponent. The actions of Nazi Germany under Adolf Hitler in the 1930s, leading to World War II, were considered to be aggressive. The invasion of Kuwait by Iraq 1990 was condemned as an act of aggression.

The term was first used officially in the Treaty of Versailles in 1919, which speaks of ‘the aggression of Germany’. It was incorporated in the covenant of the League of Nations, member states undertaking ‘to respect and preserve against external aggression the territorial integrity and existing political independence of all members’.

In 1944 the Dumbarton Oaks Conference produced a plan that, unlike the ‘call to repentance’ of the covenant, invoked no principles, but contained practical arrangements for restraining an aggressor. The conference looked to a Security Council to decide whether the conduct of a nation amounted to aggression and to shoulder the burden of keeping the peace. These proposals were incorporated in the following year in the charter of the United Nations and have since been put to the test in the cases of Korea, the Congo (Léopoldville-Kinshasa), the conflicts between the Arabs and Israelis in the Middle East, and the Turkish invasion of Cyprus in 1974.