Self Defense in an Age of Terrorism

Radical changes in the technology of weapons and the nature of adversaries now challenge the jus ad bellum that was largely codified in the United Nations Charter: Unilateral and discretionary uses of proactive military force, until then lawful, were henceforth prohibited; reactive military force was to be limited to self-defense against an armed attack, and then only until the international community could come to the assistance of a victim of unlawful military force. All uses of force were to be necessary, proportionate, and discriminating. The major powers in the Security Council undertook to cooperate to ensure the collective defense of victims of aggression