Holy See warns global nuclear disarmament, AI regulation 'imperative' at UN

With fear “the driving force” in the current global climate, nations must recommit to nuclear disarmament and the regulation of artificial intelligence, said Archbishop Gabriele Caccia, the Holy See’s permanent observer to the United Nations.

The Holy See established diplomatic relations with the U.N. in 1957, representing the Vatican City State as well as the supreme authority of the Catholic Church, including the pope as bishop of Rome and the head of the college of bishops.

In remarks Archbishop Caccia delivered to the U.N. Disarmament Commission April 8 in New York, he restated the Holy See’s call to all nations to “overcome the fallacy of nuclear deterrence” and “to accede to the Treaty on the Prohibition of Nuclear Weapons.”

Archbishop Gabriele G. Caccia, permanent observer of the Holy See to the United Nations, is pictured in a 2023 photo addressing the General Assembly at U.N. headquarters in New York City. Archbishop Caccia delivered an April 8, 2025, statement expressing concern at the continued rise of political instability and conflict. (OSV News photo/Rick Bajornas, courtesy United Nations)

Adopted by the U.N. in 2017, the treaty serves as a legally binding instrument towards the total elimination of nuclear weapons. To date, there are 94 state signatories and 73 states party to the treaty.

Neither the U.S. nor Russia, which together account for approximately 88% of the world’s nuclear weapons, have adopted the treaty.

Archbishop Caccia urged “a spirit of cooperation and mutual respect” at an upcoming session regarding the treaty in order to further its advancement.

The regulation of AI, which has increasingly transformed the defense industry, is also crucial, said the archbishop.

He cited the “multiple challenges posed by the use of emerging technologies, including artificial intelligence,” noting that their “increasing weaponization could pose further existential risks.”

In his statement, Archbishop Caccia surveyed the broader context for his calls to action.

“As political instability and conflicts continue to rise across various regions of the world, many states have turned to military solutions in an effort to safeguard their sovereignty and protect their interests,” said Archbishop Caccia.

As a result, he said, deterrence is “often seen as the essential guiding principle.”

Currently, more than 120 conflicts are taking place throughout the world, according to the International Committee of the Red Cross.

Among the most prominent are Russia’s war in Ukraine; the Israel-Hamas war; civil wars in Myanmar and Sudan; insurgencies in various African nations, as well as in Afghanistan and Pakistan; and armed gang violence that has destabilized Haiti.

Defense spending has soared worldwide, with the global total reaching a record high of close to $2.5 trillion in 2024, up more than 7% from 2023 and averaging just under 2% of nations’ gross domestic product. The European Union, the United Kingdom and Canada have accelerated defense investments, as moves by the U.S. under the Trump administration have unsettled longstanding defense alliances.

Archbishop Caccia said the shift towards defense investment “comes at a significant cost, not only in terms of financial resources but also in terms of the erosion of multilateralism, dialogue and international cooperation, which have long been the cornerstones of our collective efforts.”

He quoted St. John XXIII’s 1963 encyclical, “Pacem in Terris” (“Peace on Earth”): “There is a common belief that under modern conditions peace cannot be assured except on the basis of an equal balance of armaments … If one country increases its military strength, others are immediately roused by a competitive spirit to augment their own supply of armaments.”

Those words “resonate deeply today,” said Archbishop Caccia, adding that “the cycle of arms buildup and the logic of deterrence foster an atmosphere of suspicion and division.” This in turn, he said, “pushes the international community further from the prospect of achieving lasting peace.”

In particular, he said, “the threat of nuclear conflict is once again alarmingly close,” stressing that “it is imperative to recommit, with renewed urgency, to the path of disarmament.”

Nuclear proliferation, along with other weapons of mass destruction, “multiplies risks and offers only the illusion of peace,” while obscuring “the true path to peace,” said Archbishop Caccia.

Moreover, pursuit of nuclear deterrence fails to account for “the changing nature and complexity of conflicts and the undeniable reality that any use of these weapons would have catastrophic humanitarian and environmental consequences,” he said. “These repercussions would not discriminate between combatants and non-combatants and would cause lasting damage, harming both present and future generations.”

While a legal framework on AI may be “beyond the immediate scope” of the U.N.’s disarmament commission, he said, “the principles, guidelines, and recommendations developed here” can contribute to instruments that ensure “the use of new and emerging technologies does not fuel violent escalation of any kind, but rather benefits all humanity and peace worldwide.”

Archbishop Caccia concluded by quoting Pope Francis’ January address to diplomats accredited to the Holy See, saying, “In the face of the increasingly concrete threat of a world war, the vocation of diplomacy is to foster dialogue with all parties, including those interlocutors considered less ‘convenient’ or not considered legitimized to negotiate.

“Only in this way is it possible to break the chains of hatred and vengeance that bind and to defuse the explosive power of human selfishness, pride and arrogance, which are the root of every destructive determination to wage war,” said the pope.