War & the Requirement of Moral Certainty

“The Holy Father’s judgment is also convincing from a rational point of view. There were not sufficient reasons to unleash a war against Iraq.” — Joseph Cardinal Ratzinger, Prefect, Congregation for the Doctrine of the Faith, May 2, 2003

If there is any absolute moral law in Christianity, in Catholicism, or in Natural Law, it is “Thou shalt not murder.” In Catholic moral law, murder is the intentional unjust killing of a human being. Two popes have said that the war by the U.S. government on Iraq is unjust. Killing in an unjust war is murder.

All the “rigorous conditions” for the “rightness and goodness” of a war according to Catholic Just War doctrine have to be met with that degree of probability that Catholic moral law requires for moral certainty where the intentional destruction of human life is involved.

Although seldom taught or discussed publicly, it is a morally binding presupposition of Catholic Just War doctrine that, before a person can justifiably kill another human being in war, he must be morally certain that each and every one of the Catholic standards for determining a just war has been met. Not only met, but strictly met (Catechism of the Catholic Church, #2309). They must be strictly met before the war begins (jus ad bellum). Furthermore, they must be strictly met in conducting the war (#2312) moment to moment during the entire course of the war (jus in bello). The Catholic Just War doctrine is most certainly not a moral carte blanche for Catholic participation in wars supported by local politicians — although this is how it has often been interpreted and applied.