The Ethics of War

The document provides a comprehensive review of modern Just War theory, analyzing the criteria for entering war (jus ad bellum), conducting war (jus in bello), and ending war (jus post bellum). It highlights key tensions, such as the debate over humanitarian intervention, the morality of preventive war, and the 'moral equality of soldiers'—the question of whether combatants fighting an unjust war can still act justly in their conduct.

• There is a growing consensus that humanitarian intervention to prevent mass atrocities is a legitimate just cause for armed force, particularly following the 1994 Rwandan genocide, though disagreements remain regarding the threshold for intervention and the appropriate goals, such as whether regime change is necessary.
• Contemporary commentators generally distinguish between pre-emptive strikes, which are widely accepted as an extension of self-defense to halt imminent attacks, and preventive war, which seeks to stop a state from developing a threat-potential and is generally condemned.
• The criterion of legitimate authority traditionally limits the power to instigate war to states, but the authors argue this is an unsatisfactory gap in theory, as it fails to address whether non-state actors or repressed citizens have the right to take up arms against severe human rights violations.
• Proportionality in the resort to war (ad bellum) requires that the war be proportional to the wrong it seeks to rectify. Thomas Hurka argues that the proportionality calculus should only count positive goods related to the war's just cause, while all negative consequences must be included.
• The 'last resort' criterion is viewed as problematic because it is impossible to know with certainty when all non-violent options are exhausted. Some suggest reformulating it as a prudential requirement to seriously deliberate on all reasonable non-violent alternatives.
• In the conduct of war (jus in bello), the principle of discrimination (non-combatant immunity) is often analyzed via the doctrine of double effect, which allows for foreseeable but unintended harm to non-combatants if the action is proportionate to the military aim.
• Jeff McMahan challenges the 'moral equality of soldiers'—the idea that soldiers on both sides have an equal right to kill regardless of the justice of their cause—arguing instead that the justification for lethal force must depend on the justice of the cause.
• The emerging field of jus post bellum focuses on the moral guidelines for ending wars and managing the aftermath, suggesting that goals should include the vindication of rights and potentially 'political rehabilitation' for defeated aggressors to ensure long-term peace.

APA

Begby, E., Reichberg, G. M., & Syse, H. (n.d.). The Ethics of War. Peace Research Institute Oslo. https://cdn.cloud.prio.org/files/8732f569-2923-41bb-92e8-b9bbe259bbb7/The Ethics of War Part II Contemporary Authors and Issues.pdf?inline=true

Chicago

Begby, Endre, Gregory M. Reichberg, and Henrik Syse. The Ethics of War. Peace Research Institute Oslo, n.d. https://cdn.cloud.prio.org/files/8732f569-2923-41bb-92e8-b9bbe259bbb7/The Ethics of War Part II Contemporary Authors and Issues.pdf?inline=true.

Wikipedia

{{cite report |last1=Begby |first1=Endre |last2=Reichberg |first2=Gregory M. |last3=Syse |first3=Henrik |title=The Ethics of War |publisher=Peace Research Institute Oslo |url=https://cdn.cloud.prio.org/files/8732f569-2923-41bb-92e8-b9bbe259bbb7/The Ethics of War Part II Contemporary Authors and Issues.pdf?inline=true |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{begbyndethics, author = {Begby, Endre and Reichberg, Gregory M. and Syse, Henrik}, title = {{The Ethics of War}}, institution = {Peace Research Institute Oslo}, url = {https://cdn.cloud.prio.org/files/8732f569-2923-41bb-92e8-b9bbe259bbb7/The Ethics of War Part II Contemporary Authors and Issues.pdf?inline=true}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }