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Just Cause (in War)

  1. David Luban

Published Online: 1 FEB 2013

DOI: 10.1002/9781444367072.wbiee581

The International Encyclopedia of Ethics

How to Cite

Luban, D. 2013. Just Cause (in War). The International Encyclopedia of Ethics. .

Publication History

  1. Published Online: 1 FEB 2013


Classical just war theory distinguishes the justice of going to war (jus ad bellum) from the justice of how war is waged (jus in bello) (see War). As the theory of jus ad bellum evolved over the past millennium, a war had to satisfy multiple criteria to be just. The war must be waged (1) by a legitimate authority who is (2) acting with right intention; (3) the war must have reasonable prospects of success at attaining its goals, the importance of which is (4) proportional to the harm that the war can be expected to inflict (see Proportionality (in War)); (5) the war must be the last resort; and (6) there must be a just cause for the war. None of these criteria is clear or unambiguous, but just cause is perhaps the most contested.


  • practical (applied) ethics;
  • war and conflict