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  • John Thavis

Pope Francis and nuclear deterrence

Updated: Feb 18, 2020

As 2017 drew to a close, the potential for nuclear destruction was clearly on the mind of Pope Francis.

During the Christmas season, the Vatican circulated a card reproducing a dramatic photo from the aftermath of the U.S. bombing of Nagasaki, Japan, in 1945. Taken by Marine photographer Joseph O’Donnell, it showed a boy carrying his dead brother on his back as he waited in line at a crematorium.

On the reverse of the card is the phrase “The fruits of war” and the pope’s signature.

The image reflected a deep concern that the pope has expressed on numerous occasions since his election in 2013: that nuclear deterrence, once seen as a necessary evil, may in fact be a path to global disaster.

In November, addressing a Vatican-sponsored symposium on disarmament, the pope condemned not only the use or threatened use of nuclear weapons, but also their possession:

"Nor can we fail to be genuinely concerned by the catastrophic humanitarian and environmental effects of any employment of nuclear devices. If we also take into account the risk of an accidental detonation as a result of error of any kind, the threat of their use, as well as their very possession, is to be firmly condemned. For they exist in the service of a mentality of fear that affects not only the parties in conflict but the entire human race. International relations cannot be held captive to military force, mutual intimidation, and the parading of stockpiles of arms. Weapons of mass destruction, particularly nuclear weapons, create nothing but a false sense of security. They cannot constitute the basis for peaceful coexistence between members of the human family, which must rather be inspired by an ethics of solidarity."

This was a significant development in the church’s position on nuclear weapons. Reporters asked the pope about it in early December, and while characterizing it as his “opinion” and not a change in official church teaching, Francis said nuclear deterrence was “at the limit of what’s licit”:

"In 34 years, nuclear [development] has gone further and further and further. Today we are at the limit. This can be argued; it is my opinion, but my staunch opinion: I am convinced of it. We are the limit of what’s licit in regard to having and using nuclear weapons. Why? Because today, with so sophisticated a nuclear arsenal, we risk the destruction of humanity, or at least of a large part of humanity. For this reason I refer to Laudato Si’. What has changed? This. The development of nuclear weaponry. What has also changed…. They are sophisticated and also cruel [weaponry]; they are also capable of destroying people without touching the structures…. We are at the limit, and since we are, I ask myself this question – not as papal Magisterium, but it is the question a Pope asks – today is it licit to maintain nuclear arsenals, as they are, or today, to save creation, to save humanity, is it not necessary to go back? … We are reaching a point at which man has in hand, with this culture, the capacity to create another form of lack of culture: let’s think of Hiroshima and Nagasaki. And this was 60, 70 years ago. Destruction. And this also happens with atomic energy when we aren’t able to have complete control: think about the incidents in Ukraine. For this, getting back to weapons, which are to win by destroying, I say that we are at the limit of what’s licit."

This is not an issue that will go away soon, and it’s one that raises an implicit challenge in U.S.-Vatican relations – particularly with a U.S. president who has said he wants a big increase in the country’s nuclear arsenal.

It was Pope Francis who, when addressing the United Nations in 2015, called on nations to work for a “complete prohibition” on nuclear weapons, a line that drew applause and was quickly forgotten.

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