Pope Francis speaks during a news conference onboard the papal plane on his flight back from a trip to Thailand and Japan, Monday, Nov. 26, 2019. (Remo Casilli/Pool Photo via AP)
From TIME.com:
Pope Francis is planning to change official Catholic Church teaching to declare the use and possession of atomic weapons as “immoral,” a move that makes clear that his rejection of the Cold War-era doctrine of deterrence is to be official church policy.
Francis had declared the possession of nuclear weapons immoral on Sunday in Hiroshima during an emotional encounter with survivors of the U.S. atomic bomb.
On Tuesday, during a press conference en route home from Japan, Francis indicated that his Hiroshima address should be considered part of his magisterium, or official church teaching.
“This must go in the Catechism of the Catholic Church,” he said, referring to the published compendium of official church teaching.
“Not just the use, also the possession,” he said. “Because an accident of possession, or the insanity of a leader or someone, can destroy humanity.”
The shift upended three decades of the Vatican’s tacit acceptance of nuclear arsenals. Starting in 1982, St. John Paul II had held that deterrence could be morally acceptable in the interim as long as it was used as a step toward mutual, verifiable disarmament.
In the ensuing years, however, the Holy See has watched as arms control treaties collapsed, new nuclear powers emerged and the policy of assured mutual destruction resulted in a permanent stockpiling of bombs.
Francis also went further Tuesday in his comments on nuclear energy, saying he would rule out its use until scientists can offer “total security” to ensure that accidents, natural disasters and “crazed” individuals won’t destroy humanity and the environment with nuclear fallout.
Francis offered his “personal opinion” that went beyond the “concern” he expressed in public a day earlier during a meeting with survivors of the 2011 Fukushima nuclear disaster.
The Japanese government strongly backs nuclear energy despite the 2011 “triple disaster,” in which three Fukushima nuclear reactors partially melted down after an earthquake triggered a tsunami. The disaster spewed nuclear fallout across the region and at one point forced the evacuation of 160,000 people.
“I have a personal opinion,” Francis said. “I would not use nuclear energy as long as there’s not a total security on the use.”
Catholicism Pure & Simple 
Does The Holy Father think that any “bad actor” of this World, present or future, actually cares what Church Teaching is on use of nuclear weapons? May be the threat of being nuked in retaliation for first use is what keeps the lid on Armageddon? Just wondering Holy Father.
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He should acknowledge that his personal opinion should never enter the Catechism! This is not what the Church teaches or has taught through the ages and is not related to anything specific in the Bible. Adding it would make it “not a catechism”. He might as well call it the “popular thoughts handbook.”
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Why only Nuclear weapons? Are conventional weapons of any kind moral? Since nobody is dying by Nuclear weapons today – how can this make sense?
Maybe Pope should add to the Catechism “possession of any weapon is immoral – those who benefit from their use in any way are not Christians”. Then either have his bodyguards dispose of their guns, or quit being pope.
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