The meaning of collective security

Collective security postulates the institutionalization of the lawful use of force in the international community. What is required is a multilateral treaty, whereby contracting parties create an international agency vested with the power to employ force against aggressors (and perhaps other law-breakers). Such an instrument is basically ‘introverted’ in character (designed against a potential future aggressor from among the contracting parties), unlike a collective self-defence treaty (see supra, ch. 9, B) which is ‘extroverted’ (envisaging aggression from outside the system). Collective security shares with collective self-defence the fundamental premise that recourse to force against aggression can (and perhaps must) be made by those who are not the immediate and direct victims. But self-defence, either individual or collective, is exercised at the discretion of a single State or a group of States. Collective security operates on the strength of an authoritative decision made by an organ of the international community.

The system of collective security has its roots in the League of Nations. Article 10 of the Covenant empowered the League's Council to advise Member States on the means to be taken in case of aggression or threat of aggression. Article 11 declared that any war or threat of war, whether or not immediately affecting any Member, was a matter of concern to the whole League, which had to take action as required to safeguard peace among nations.