Holy See: Outer space and AI must not be weaponized

By Devin Watkins

Msgr. Daniel Pacho, Undersecretary for the Holy See’s Multilateral Sector of the Secretariat of State, has renewed the Church’s call for disarmament.

Addressing the UN-led 2026 Conference on Disarmament in Geneva on Wednesday, he said humanity is at “a critical juncture,” recalling Pope Leo XIV’s warning in January that war is “back in vogue, and a zeal for war is spreading.”

Msgr. Pacho lamented that diplomacy based on force is replacing dialogue and consensus-seeking, saying this shift has undermined multilateral discussions on disarmament, including the Conference on Disarmament.

He upheld disarmament as a “moral imperative” that ensures weapons are never used again in aggression to harm others.

“Disarmament is not an end in itself,” he said. “It is a key tool for building trust and achieving just and lasting peace, and therefore significant for promoting integral human development.”

Msgr. Pacho reiterated the Holy See’s opposition to nuclear proliferation, expressing its concern for the “existential threat” they pose to humanity.

Nuclear deterence, he said, is based on the irrational belief that international relations should be based on the threat of force rather than on justice, law, and trust.

When the “dangerous path of deterence” replaces all diplomatic efforts, he said, “humanity and our planet as a whole risk being pushed towards the edge of devastation and destruction.”

In this context, Msgr. Pacho repeated the Holy See’s invitation for nuclear-armed nations to engage in good-faith negotiations to reduce and eventually eliminate their arsenals.

The Holy See’s representative went on to consider that outer space is quickly becoming a forum for great power conflict.

“The militarization of outer space is already a reality and will lead to its weaponization, unless concrete steps are taken to build trust and enhance collective security and responsibility,” he said.

Any major conflict in outer space, he added, would have devastating effects for our generation and those of the future.

“It is therefore essential,” he said, “that the exploration and use of outer space is preserved for peaceful purposes only, as a common ‘province of all mankind’ in accordance with the 1967 Outer Space Treaty.”

Msgr. Pacho then turned to the weaponization of artificial intelligence, noting that AI is increasingly dehumanizing the way that wars are waged.

“When autonomous weapons ‘become’ the combatants,” he said, “the unique human capacity for moral judgment and ethical decision-making disappears, as does the burden of responsibility, dangerously lowering the threshold for conflict.”

Humans must therefore remain in control in all use of force, he said, calling for a moratorium on the development and use of lethal autonomous weapons systems.

In conclusion, Msgr. Pacho urged the Conference on Disarmament to seek paths to verify how nations are using emerging weapons platforms, while confronting expanding military expenditure with treaties to limit armaments.

“For humanity to move towards authentic and lasting peace,” he said, “it is crucial that this Conference on Disarmament achieves concrete and lasting disarmament agreements for the common good of all peoples.”