FOURTH SUNDAY OF EASTER, APRIL 26, 2026
Pope Leo's calls for peace and President Trump's criticisms of the Pope have been major news this week. In light of the controversy, I want to explain the Catholic Church's teaching on war.
First, the Church's teaching on war is ancient, first articulated by Saint Augustine in the 5th century. There is no new teaching. Pope Leo did not create a teaching on war and he is not speaking only of his opinion. The Holy Father is referencing the teaching of the Catholic Church and based on that teaching, he reflects on the war in Iran. People can disagree about the application of the teaching to the Iran war, but we are not free as Catholics to disagree with the teaching. The teaching is doctrine; the application of the teaching is interpretation of the doctrine.
Throughout the centuries many Christians, reading the words of Jesus about loving your enemies and turning the other cheek when someone strikes you, concluded that no war is justified, that only absolute pacifism is consistent with the teaching of Jesus. While this is a completely rational reading of the Gospel, it is not the teaching of the Church. Based on Saint Augustine, the Church teaches that war is allowed under limited circumstances.
- In 1983, the US Catholic bishops issued a statement summarizing the Church's ancient teaching on war. In The Challenge of Peace, the bishops said that "Catholic teaching begins in every case with a presumption against war and for peaceful settlement of disputes. In exceptional cases, determined by the moral principles of the just-war tradition, some uses of force are permitted." The first principal is that the presumption is against war. In other words, the burden of proof is on the one trying to justify war, not on the one opposing war.
- In that document, again articulating ancient teaching, the bishops said, "Every nation has a right and duty to defend itself against unjust aggression," however, "Offensive war of any kind is not morally justifiable." Therefore, a nation can only go to war to defend from an unjust aggression. It is always immoral for a country to start a war. Of course, that raises the question: must a country wait until the other country fires the first shot or drops the first bomb. No, not necessarily. If there is an imminent and certain threat of an attack, a nation may defend before the attack happens. The key word is "defend". A just war is defensive, never offensive.
- The catechism of the Catholic Church explains the other conditions for a just war: a. The damage inflicted by the aggressor on the nation or community of nations must be lasting, grave, and certain; b. All other means of putting an end to the aggression must have been shown to be impractical or ineffective; c. There must be serious prospects of success;
- The use of arms must not produce evils and disorders graver than the evil to be eliminated. The power of modern means of destruction weighs very heavily in evaluating this condition.
Moreover, in the course of war, it is categorically wrong to attack civilians or to attack the food and water supply of civilian populations. That means, a nation cannot attack schools, hospitals, private homes, power plants, water plants, crops and all that is needed for life. The wars that have happened in my life time (Vietnam, Iraq, Afghanistan, etc.) have caused much loss of life of civilians, including children. In modern wars it may be safer to be a soldier than a civilian since more civilians are killed than soldiers! Food production has been damaged and hunger has been the result. The Iran war began with an American attack on a school filled with children; though the killing of hundreds of children was not intended, it is still a serious risk in war and the country which kills children is in the wrong.
While politics is at the heart of a nation's decisions, political decisions ought to be based on sound moral principles. In this bulletin column, I am not giving my opinion about the war against Iran, but articulating the clear teaching of the Church so that you can decide if this war is just under the Church's ancient teaching.
Regardless of a person's opinion about the moral justification for this war, every person must long for peace. Boasting and bellicose talk is never right for a country at war. Even if a war is justified, one must regard the enemy as human with dignity and rights.
Pope Leo is right to remind us of our Church's consistent teaching and he is right to lament war and to urge prayers and actions for peace. No decent human being can glory in war or war talk. The Pope is not talking politics, but morality and theology. That said, you can draw your own conclusions about this war.
