Just War Theory

Just war theory describes a set of principles designed to regulate the conduct of warfare, including justifications for going to war (jus ad bellum), conduct during war (jus in bellum), and justice after war (jus post bellum). Just war theory can be used by history teachers as a conceptual framework for analyzing and comparing different conflicts in history.


When resorting to war is just (Jus ad Bellum - “Right Before War”):

  1. Just Cause: The war must be fought for a just cause.
  2. Right Intention: The intention of those fighting the war must conform to the just cause.
  3. Legitimate Authority: The war must be waged by a legitimate authority.
  4. Last Resort: War must be the option of last resort.
  5. Chances of Success: War must stand a reasonable chance of success.
  6. Proportionality: The harm that war causes must be proportionate to the good that it brings about.


Restrictions on waging war (Jus in Bello - “Right in War”):

  1. Necessity: Combatants must only carry out operations necessary to their legitimate military objectives.
  2. Proportionality: The harms that any particular operation causes must be proportionate to the good that it brings about.
  3. Discrimination: Only combatants are legitimate targets of attack, noncombatants must not be deliberately harmed.


What is required following war (Jus post Bellum - “Right after War”):

  1. Reconstruction: Victorious belligerents must assist in the post-war reconstruction of the vanquished nations.
  2. Reparations: Unjust belligerents must pay compensation and other forms of restitution to their victims.
  3. Justice: Victorious belligerents may subject wrongdoing individuals to fair criminal procedures.

For more on Justice After War, see: Jus Post Bellum: An Example of a Conceptual Framework in Social Studies.

Reference:

Taylor, I. (2017). Just War Theory and the Military Response to Terrorism. Social Theory & Practice, 43(4)