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The Just War Theory

Conditions for a just war...

Just War Theory: The idea that for a war to be morally justifiable (just) it must meet a number of conditions.

Nature, History and Importance

The Just War theory is used by governments as a form of guidance when considering whether a war is the right course of action. It provides a way for them to examine all aspects of a potential war, encouraging them to consider other ways of resolving conflict.

In the 4th century, St. Augustine first taught the idea of a just war as a Christian concept. He believed that the only reason to go to war was to bring about peace. Augustine recognised that war was always going to be around, but he tried to bring together the teachings of Jesus about peace, with the obligations of Roman citizens - including Christians - to fight for their country when required to.

"We do not seek peace in order to be at war, but we go to war that we may have peace." Augustine.

Thomas Aquinas further developed Augustine's ideas in the 13th century, establishing conditions for a framework of a just war. War Aquinas' conditions form the basis of today's Just War theory, adding to his conditions on whether a war should be fought (jus ad bellum) to how it should be fought (jus in bello).

Conditions of a Just War 

Today there are six conditions of the Just War theory that should be met in order for it to be thought of as 'just.'

  • The war must be for a just cause, for example, self-defence or protection of a weaker country.
  • The war must be lawfully declared by a lawful authority.
  • The intention behind the war must be good.
  • All other ways of resolving the problem should have been tried first.
  • There must be a reasonable chance of success.
  • The means used must be in proportion to the end that the war seeks to achieve.
What do you think of the Just War criteria? Does it influence your opinion of war? Is there anything worth dying for?