Just War Theory

In order to be just, a war must meet the following criteria before the use of force (jus ad bellum):

  • Just cause: The reason for going to war needs to be just and can therefore be recapturing things taken or punishing people who have done wrong.
  • Comparative justice : While there may be rights and wrongs on all sides of a conflict, to override the presumption against the use of force, the injustice suffered by one party must significantly outweigh that suffered by the other.
  • Legitimate authority: Only duly constituted public authorities may use deadly force or wage war
  • Right intention: Force may be used only in a truly just cause and solely for that purpose—correcting a suffered wrong is considered a right intention, while material gain or maintaining economies is not.
  • Probability of success: Arms may not be used in a futile cause or in a case where disproportionate measures are required to achieve success;
  • Last resort: Force may be used only after all peaceful and viable alternatives have been seriously tried and exhausted.

Once war has begun, just war theory also directs how combatants are to act (Jus in bello):

  • Discrimination: Just war conduct should be governed by the principle of discrimination. The acts of war should be directed towards the inflictors of the wrong, and not towards civilians caught in circumstances they did not create.
  • Proportionality: Just war conduct should be governed by the principle of proportionality. The force used must be proportional to the wrong endured, and to the possible good that may come.
  • Minimum Force: Just war conduct should be governed by the principle of minimum force. This principle is meant to limit excessive and unnecessary death and destruction. It is different from proportionality because the amount of force proportionate to the goal of the mission might exceed the amount of force necessary to accomplish that mission..

Operational Law Handbook The Operational Law Handbook is a "how to" guide for judge advocates practicing operational law. It provides reference and describes tactics and techniques for the practice of operational law. It supports the doctrinal concepts and principles of the Law of Land Warfare FM 27-10 . The handbook provides information on the legal basis for the use of force, law of war (LOW), human rights, rules of engagement, emergency essential civilians supporting military operations, contingency contractor personnel, foreign and deployment, criminal law, environmental law, fiscal law, deployment contracting and battlefield acquisition, intelligence law and interrogation operations, administrative law, international agreements & SOFAs, legal assistance, combatting terrorism, domestic operations, noncombatant evacuation operations, special operations, civil affairs, air, sea, and space law, detainee operations, reserve component Soldiers and operations, joint operations, military decision making process & operations plans, Center for Law and Military Operations (CLAM), internet websites for operational lawyers.

Law of War Handbook should be a start point for Judge Advocates looking for information on the Law of War. It is the second volume of a three volume set and is to be used in conjunction with the Operational Law Handbook (JA422) and the Documentary Supplement (JA424). The Operational Law Handbook covers the myriad of non-Law of War issues a deployed Judge Advocate may face and the Documentary Supplement reproduces many of the primary source documents referred to in either of the other two volumes. The Law of War Handbook is not a substitute for official references.

Legal Resource links from the USAF Air War College
JustWarTheory.com is a free, non-profit, critically annotated aid to philosophical studies of warfare.

"Improving the Fighting Position": A Practioners Guide to Operational Law Support to the Interrogation Process

The Law of War: Can 20th-Century Standards Apply to the Global War on Terrorism? by LTC David P. Cavaler, US Army (Ret.), Combat Studies Institute (CSI) Global War on Terrorism Occasional Paper 9