Pope Leo warns of AI fueling warfare in first major theological document

Pope Leo XIV released his first encyclical, *Magnifica Humanitas*, addressing the ethical risks of artificial intelligence and its role in modern warfare. The document warns that unchecked AI development could exacerbate global conflicts, emphasizing the need for rigorous ethical constraints and robust legal frameworks to prevent misuse. The pope rejects the traditional 'just war' theory, stating military force should only be used for self-defense, and urges leaders to prioritize dialogue, diplomacy, and forgiveness over violence. The encyclical highlights concerns about AI centralizing power in the hands of a few, drawing parallels to the biblical story of the Tower of Babel to warn against dehumanizing technological dominance. Pope Leo calls for diverse perspectives in AI development, ensuring the technology respects human dignity, protects jobs, and aligns with environmental and social justice principles. He stresses that political systems must oversee AI responsibly to prevent harm to civilian populations. The pope’s critique follows recent tensions with U.S. Vice President JD Vance, who cautioned against the pontiff’s theological stance on military action. Leo reiterated his call for humanity to confront AI’s challenges with faith, reason, and attention to the needs of the poor and the environment. The document, presented at the Vatican on Monday, expands beyond technological concerns to address broader crises facing society. Traditionally, encyclicals are letters to the Catholic Church, but modern popes, including Francis, have used them to address global audiences. Leo’s text is seen as a landmark for his papacy, framing AI as both a tool and a threat that demands ethical stewardship. The pope’s warnings reflect growing concerns about AI’s impact on warfare, governance, and human rights, positioning the Vatican as a key voice in shaping the technology’s future.