The recent Popes have spoken against nuclear weapons and nuclear proliferation. They have repeatedly called for total disarmament worldwide. They have also condemned the use and even the possession of these weapons.
Second Vatican Council: “Any act of war aimed indiscriminately at the destruction of entire cities or of extensive areas along with their population is a crime against God and man himself. It merits unequivocal and unhesitating condemnation”. [Gaudium et Spes]
Pope John 23: “Moreover, even though the monstrous power of modern weapons does indeed act as a deterrent, there is reason to fear that the very testing of nuclear devices for war purposes can, if continued, lead to serious danger for various forms of life on earth. Hence justice, right reason, and the recognition of man’s dignity cry out insistently for a cessation to the arms race. The stock-piles of armaments which have been built up in various countries must be reduced all round and simultaneously by the parties concerned. Nuclear weapons must be banned.” [Pacem in Terris]
Pope Francis: “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.” [Address 2017]
The destruction of population centers as the targets for a weapon of mass destruction is intrinsically evil, as it is a form of mass murder. As discussed on this blog previously, the destruction of Hiroshima and Nagasaki were grave crimes against humanity.
However, the possession of nuclear weapons has not been condemned by the Magisterium definitively. The above assertion by Pope Francis does not meet the conditions for an infallible teaching, and there seems to be no support for a claim of infallibility under the ordinary and universal Magisterium. Possession remains an open question. As for the use of nuclear weapons in warfare, the above quote from the Second Vatican Council does not condemn all use, but only a use which would directly kill large numbers of civilians.
Suppose a large armada of warships is headed for the United States coastline, to attack our cities. If they could be stopped by a nuclear missile, with limited civilian casualties, saving many lives, the use of these weapons might be justified. Such a use would not be intrinsically evil, as the target is military and the purpose is defending millions of innocents.
Contrary to the position of Pope Francis, John 23 stated that the possession of nuclear weapons does function as a deterrent. And though all the Popes agree what nuclear disarmament is a necessary goal for the benefit of humanity, possession in the interim would not be intrinsically evil.
Suppose that the U.S. unilaterally disarms. Will Russia or China attack us? Probably not. But the mere possibility of such an attack, against which we could offer no substantial retaliation, would disadvantage the U.S. in international relations, allowing both those nations to possibly expand by conquering their neighbors. The harm done to innocent must be given its proper moral weight, in such a case.
Suppose that the U.S. and other superpowers disarm. What will happen if a nation led by unreasonable persons, such as North Korea or Iran, obtains nuclear missiles? North Korea presently has nuclear bombs. Their alleged intention to negotiate a disarmament has not yet reached its goal (and might never). A disarmed U.S. and/or disarmed Russia and China would allow small rogue nations to make grave threats, thereby putting much of the world under their control. Do what the dictator in nation X says, or he will nuke one of your cities. We would be subject to nuclear blackmail, and would lose our freedoms if not our lives.
My work in eschatology gives me some additional perspective on this topic. I believe that Iran will obtain nuclear bombs, and subsequently nuclear missiles. I also believe that the Arab Muslim nations of the Middle East and northern Africa will unite under the leadership of Iran and ISIS (in Iraq) with the goal of conquering the West. They will use nuclear weapons in World War 3. They will succeed in conquering Europe partly because the West is not willing to use nuclear weapons, and they are willing.
Then, after World War 3, during the occupation of Europe, a new leader will take control of that vast territory (Europe, the Middle East, northern Africa, excluding Israel) and will gain control of many ICBMs. He will threaten the free nations with nuclear annihilation if we do not convert to his extremist version of Islam and submit to his authority. The U.S. and our Allies will not submit to this threat, leading to World War 4, an all-out nuclear war. We defeat this enemy, but at great cost. However, without nuclear weapons, we would be conquered by that dictator, forced to submit to Islam and be subjugated to a maniacal dictator.
The use of nuclear weapons in war can be justified, against military targets, in an extreme situation. And therefore the possession of said weapons is also possibly justified.
Can a Catholic take the opposite position, that the use and possession of nuclear weapons is intrinsically evil and always gravely immoral? I think that position is tenable, given the current state of magisterial teaching. But I don’t think that Church teaching, at present, requires it.
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