KEY WEST, Florida – Today in Japan, which began last night in the States, brought the expected highlights of Pope Francis’s Nov. 20-26 trip to Thailand and Japan in visits to Hiroshima and Nagasaki, the two Japanese cites incinerated by U.S. atomic weapons during the Second World War.

“One of the deepest longings of the human heart is for security, peace and stability,” Francis said on Sunday, speaking in the Nagasaki Atomic Bomb Hypocenter park during driving rain.

“The possession of nuclear and other weapons of mass destruction is not the answer to this desire; indeed they seem always to thwart it,” he said.

News headlines around the world generally are carrying some form of, “Pope condemns nuclear weapons,” which is true as far as it goes but not terribly informative. The Catholic Church has never approved of nuclear weapons, so those headlines have a somewhat “dog bites man” feel.

In the 13th century, St. Thomas Aquinas laid the basis for what would become known as the “Just War” tradition, which was later elaborated by members of the Thomistic school. One core principle is known as “proportionality,” meaning that one cannot morally use more force than is necessary to deter an aggressor. Further, violence has to be discriminate, meaning directed at combatants rather than civilians.

Had Thomas been around in 1945, it doesn’t require a great leap of imagination to guess what his assessment of nuclear warfare likely would have been.

More recently, every pope over the last seven decades has supported nuclear disarmament, so there’s nothing novel in Francis doing the same.

What is a bit more striking with Francis is his unequivocal rejection not merely of the use, or threat of use, of nuclear weapons, but their very existence. In effect, Francis has capped a development in Church thinking from a grudging and conditional acceptance of the concept of deterrence under St. John Paul II, which was forged during the Cold War, to a sweepingly abolitionist position today.

What’s changed isn’t so much the moral principles involved, but the diagnosis of the global situation.

The major international agreements on nuclear weapons, such as the Nuclear Test Ban Treaty, were adopted in the Cold War era when a perceived rough nuclear equilibrium among the major powers was perceived as necessary to maintain the peace. Today’s situation is more fluid and dangerous, with threats coming not merely from the usual nuclear powers but rogue states and non-state actors such as terrorist networks.

In that context, the very existence of weapons with the destructive power of nuclear arms is arguably, de facto, destabilizing and a threat to peace, hence the extension of the Church’s traditional position from containment to elimination.

That’s a shift, by the way, that was well underway before Francis arrived; in 2010, when Pope emeritus Benedict XVI was still in charge, the Vatican declared that “the conditions that prevailed during the Cold War, which gave a basis for the Church’s limited toleration of nuclear deterrence, no longer apply.”

What’s interesting about the pope’s Hiroshima and Nagasaki stops, therefore, isn’t really the substance of what Francis is saying, but rather the fact he appears to be ratcheting up the emphasis and visibility with which he’s saying it.

A pope standing in those two spots and thundering away at nuclear weapons obviously isn’t the same as issuing a bland diplomatic communique for the next round of negotiations over the Comprehensive Nuclear-Test-Ban Treaty, or mentioning disarmament as one item on a laundry list of desired social goods in the pope’s year-end speech to diplomats at the Vatican.

In effect, today marks Francis’s bid to become what social scientists call a “norm entrepreneur” on nuclear disarmament, a possibility suggested in May 2018 by Gerard Powers of Notre Dame’s Kroc Institute for International Peace Studies and a former advisor to the U.S. bishops’ conference on nuclear issues.

As coined by Cass Sunstein, a “norm entrepreneur” is someone who aims to change social conventions, including moral conventions. If it works, such efforts can lead to a “norm cascade,” which triggers an upheaval in attitudes followed by a new sense of what’s acceptable and what isn’t.

The Catholic Church, of course, has been on the receiving end of one of those “norm cascades” in recent years in the form of the clerical sexual abuse scandals, in which a behavior which previously was ignored or quietly tolerated suddenly generates massive public outrage, producing a completely new normative landscape.

It’s anyone’s guess whether Catholicism under Francis can engineer such a cascade on nuclear disarmament. Given the current Realpolitik of the early 21st century, one supposes the smart money would have to be against it.

What’s for sure, however, is this: If you were going to pick two places anywhere in the world to try to start the boulders tumbling toward an avalanche, Hiroshima and Nagasaki undoubtedly would be the ones.

Follow John Allen on Twitter: @JohnLAllenJr

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