Why Leo XIV’s Encyclical Is Contradictory on Just War
Magnifica Humanitas, drawing on Fratelli Tutti, offers two reasons for moving beyond just war theory: first, that nearly every war in recent decades has been presented as justified, and second, that modern weapons make war an unacceptable solution.
Spieker finds neither argument convincing. Regarding the first, he writes: “If everyone who wages a war appeals to this doctrine, it remains necessary to examine who is justified in doing so and who is not.”
He adds: “Those who falsely invoke this doctrine will face criticism or rejection. But that does not make the doctrine of just war obsolete.”
Nor do modern weapons invalidate the doctrine: “If a particular weapon or its use cannot be justified, then that use must be rejected. But this does not render the doctrine of just war invalid; on the contrary, it confirms it.”
“Legitimate Defense” Is Just War Theory
Spieker is particularly critical of the encyclical’s claim that just war theory should be overcome “without prejudice to the right of legitimate defense.”
He notes: “The encyclical avoids any further reflection on what ‘legitimate defense in the narrowest sense’ actually means.”
For Spieker, this creates a contradiction. Once one attempts to define legitimate defense, one inevitably returns to the criteria traditionally provided by just war theory.
What If Diplomacy Fails?
The encyclical presents dialogue, diplomacy, and forgiveness as means that are “far more effective” in promoting human life than the use of force. Spieker does not dispute their value. His criticism is that the document leaves a crucial question unanswered:
“Once again, the encyclical avoids the question of what should happen when all these means fail.”
He adds that this too can have “devastating consequences for the civilian population.”
Just War Returns Through the Back Door
According to Spieker, the inconsistency becomes most apparent in the section on artificial intelligence and warfare. There, Magnifica Humanitas itself states that “armed force should be used only as a last option in cases of legitimate defense” and insists that “precise criteria for moral judgment must be identified.”
Among those criteria are identifiable chains of responsibility and the distinction between combatants and non-combatants.
For Spieker, these are precisely the kinds of criteria associated with the traditional doctrine of just war. In his view, the encyclical ultimately returns to the very framework it seeks to leave behind.
Picture: Manfred Spieker © J.-H. Janßen, wikipedia, CC BY-SA, #newsJmrryteejg