Magnifica Humanitas devotes an entire chapter to the military use of artificial intelligence. Pope Leo XIV warns that AI can lower the threshold for the use of force and feed a culture in which victims are reduced to data. His appeal is categorical: no algorithm can make war morally acceptable.

The Pope argues that the digital revolution is modifying the grammar of conflict. Visible war is now joined by hybrid forms: cyberattacks, information manipulation, influence campaigns and the automation of strategic decisions. AI accelerates these processes in a context where many technologies are intrinsically ambivalent: what is created to protect can quickly become a tool of attack.

AI does not free conflict from its inhumanity. It can make it faster, more impersonal and more opaque, turning defense into predictive operations and victims into data points. In this way, it accustoms us to the idea that violence is inevitable and must merely be optimized.

The Pope condemns the development of fully autonomous weapons, in which the decision to kill is delegated to automated systems. Moral judgment cannot be reduced to calculation. It implies conscience, personal responsibility and the recognition of the other as a person. For that reason, it is not legitimate to entrust lethal or irreversible decisions to artificial systems.

The encyclical demands traceability and accountability. For every system used in warfare, it must be possible to reconstruct decisions so that responsibility does not dissolve into the machine. Those who plan, train, authorize and deploy such systems must remain identifiable and answerable.

The Pope also denounces the technological arms race, including massive contracts between major technology companies and military institutions. AI may strengthen defense and civilian protection, but it can also lower the threshold for force, obscure responsibility and create a culture in which the enemy becomes a data point and the victim a collateral calculation.

The critique goes beyond autonomous weapons. The encyclical diagnoses the culture of power that normalizes war. Regional conflicts, escalation, cross-threats and territorial ambitions become habitual, while ethical criteria that once limited the use of force erode.

The Pope denounces the connection between economic interests, military systems and political decisions. War becomes a market, and arms industries benefit from conflicts that continue and expand. He also warns against the loss of historical memory, which makes it easier to rewrite the past and forget the lessons of catastrophe.

Against this culture of power, Leo XIV proposes five paths: disarming words, building peace in justice, adopting the gaze of the victims, cultivating a healthy realism and renewing dialogue and multilateralism. Dialogue remains the principal instrument of coexistence among persons and peoples.

Compared with other global actors, the Vatican appears as one of the clearest voices condemning the military use of AI and demanding effective human control. Its alternative is not naivety, but a refusal to accept the idea that technology should make violence easier to exercise and easier to forget.