The United Nations Charter, Article 2(4) states, 'All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.' This principle is also encapsulated within customary international law. Pursuant to the Charter, a state may only use force or the threat of force as self-defense or after authorization from the United Nations Security Council. The right of self-defense is not unlimited, it allows a state to use force in matters where there is an instant and overwhelming need to act, but requires a measure of proportionality. Article 51 of the Charter states, 'Nothing in the present Charter shall impair the inherent right of individual or collective self-defense if an armed attack occurs… Measures taken by Members in the exercise of this right of self-defense shall be immediately reported to the Security Council and shall not in any way affect the authority and responsibility of the Security Council under the present Charter to take at any time such action as it deems necessary in order to maintain or restore international peace and security.'


After the events of September 11, 2001, the United Nations Security Council reestablished the right to self-defense as it applies in regards to international incidents of terrorism. International law, specifically in regards to the use of force, is developing to permit preemptive strikes by states that reasonably believe an attack upon them is imminent. This also requires an additional evaluation of necessity and proportionality. Though these developments are controversial, they signal the future direction of this area of international law.

International Law Instruments

United Nations Charter (1945)

Pakistan officially joined the United Nations on September 30, 1947