Just War Theory

• The 'Just War Theory' refers to a theory that is used to decide whether a war is 'just' or 'fair'
• St. Augustine began the tradition of the just war theory. However, St Thomas Aquinas determined that there should be guidance on whether going to war is the Christian thing to do. These guidelines outlined the main conditions that could justify Christians partaking in war
• The 'Just War Theory' suggests that a war is 'just' (right) if certain conditions are met


  1. War must be declared and controlled by a lawful authority e.g. government
  2. War should be last resort. Every other possibility of resolving conflict has been attempted
  3. There must be right intentions, good should always be promoted and evil avoided. There should be a clear aim that once these intentions are achieved, the fighting must end
  4. There must be a reasonable chance of success/ a high likelihood of victory
  5. Reasonable force should be used, and proportionality should be considered.
• Although the Catholic Church considers violence and war morally wrong, sometimes it is seen as necessary to protect and defend innocence
• What do Jews say about conflict?

  Just war theory can also be supported by Jews because Jewish teachings do say that war to achieve justice and to tackle oppression is acceptable. However, Jews do not follow the theory specifically. Instead, they divide war into 3 categories:

  1. Milchemet Mitzvah - war commanded by God
  2. Milchemet Reshut - optional war e.g. Just War
  3. A pre-emptive war - defensive war
• Most Jews do not support war unless they believe it to be essential, for example in self-defence "If a person intends to kill you, be first to kill him" (Talmud). --> Both Catholics and Jews may decide to take a stance against conflict by being pacifists or conscientious objectors