Michael KreponThe Catholic Church and the Bomb

hannah-hNote to ACW readers: This week, guest contributor Hannah Haegeland continues a series of posts on the morality of nuclear deterrence. Strategic modernization programs, which are proceeding on a significant scale in the United States, Russia, China, Pakistan, and India, are grounded in concepts of nuclear deterrence that are alien to all religious traditions. Periodic reminders appear warranted. Hannah is a Research Associate at the Stimson Center and a Scoville Fellow. — MK


What does the Catholic Church have to say about the Bomb? It is important to distinguish between the Church’s support of specific policies and her guidance on matters of faith. The Church speaks with authority on issues of faith and personal morality, while offering suggestions and advice on public policy. The Church does not tell Catholics how to vote.

According to the Catechism of the Catholic Church, the “legitimate defense by military force” requires that action taken be a last resort, in response to “lasting, grave, and certain” damage by an aggressor with “serious prospects of success.” Even so, the use of force must not “produce evils and disorders graver than the evil to be eliminated.” While the Catechism does not go into specifics on the morality of nuclear weapons, pastoral letters and statements by popes have.

The key document in Church history on nuclear weapons is a 64-page pastoral letter by the U.S. National Conference of Catholic Bishops issued in 1983, when U.S.-Soviet relations were roiled and nuclear negotiations broken off. It remains the most detailed and thorough authoritative text from the Church on this issue. Addressing American and NATO policies by name, the bishops posit that first use is never morally justifiable:

We do not perceive any situation in which the deliberate initiation of nuclear warfare, on however restricted a scale, can be morally justified. Non-nuclear attacks by another state must be resisted by other than nuclear means.

Further, the Church has been skeptical of how subsequent use or excursions related to “limited” nuclear war could fit with “just-war” requirements that there be “a reasonable hope of success in bringing about justice and peace”:

We must ask whether such a reasonable hope can exist once nuclear weapons have been exchanged…and we hope that leaders will resist the notion that nuclear conflict can be limited, contained or won in any traditional sense.

Notably, the pastoral letter included a “strictly conditional moral acceptance of deterrence” emphasizing that it cannot be “a long-term basis for peace”:

Although we acknowledge the need for deterrence…There are moral limits to deterrence policy as well as to policy regarding use. Specifically, it is not morally acceptable to intend to kill the innocent as part of a strategy for deterring nuclear war.

Detailing their limited definition of the moral acceptability of nuclear deterrence, the bishops challenged US war-fighting strategies at a basic level:

If nuclear deterrence exists only to prevent the use of nuclear weapons by others, then proposals to go beyond this to planning for prolonged periods of repeated nuclear strikes and counterstrikes, or “prevailing” in nuclear war, are not acceptable. They encourage notions that nuclear war can be engaged in with tolerable human and moral consequences. Rather, we must continually say “no” to the idea of nuclear war.

Additionally, the letter calls for “immediate, bilateral verifiable agreements to halt the testing, production and deployment of new nuclear weapons systems.”

During and following the Cold War, Pope Saint John Paul II and his representatives spoke out many times against nuclear weapons and the dangers of nuclear deterrence security frameworks. The 1983 bishops’ letter relies upon that guidance, frequently quoting the Holy Father:

Pope John Paul II judges that deterrence may still be judged morally acceptable, “certainly not as an end in itself but as a step on the way toward a progressive disarmament….

“The logic of nuclear deterrence cannot be considered a final goal or an appropriate and secure means for safeguarding international peace.”

In a follow-up letter by the US Council of Bishops in 1998, they revised their previous emphasis on the limited value of nuclear weapons for deterrence purposes:

For the past fifteen years, and particularly in the context of the Cold War, we…have reluctantly acknowledged the possibility that nuclear weapons could have some moral legitimacy, but only if the goal was nuclear disarmament. It is our present, prayerful judgment that this legitimacy is now lacking.

The bishops’ 1998 letter also quotes John Paul II’s revised emphasis in a statement by his United Nations representative:

In clinging to their outmoded rationales for nuclear deterrence [NWS] are denying the most ardent aspirations of humanity… Nuclear weapons are incompatible with the peace we seek for the 21st century. They cannot be justified. They deserve condemnation. The preservation of the Nonproliferation Treaty demands an unequivocal commitment to their abolition.

Since Francis became Pope in 2013, the Church has shown renewed vigor in her advocacy for nuclear disarmament. Last month, his statement to the UN General Assembly affirmed that,

An ethics and a law based on the threat of mutual destruction – and possibly the destruction of all mankind – are self-contradictory and an affront to the entire framework of the United Nations, which would end up as “nations united by fear and distrust”. There is urgent need to work for a world free of nuclear weapons, in full application of the Non-Proliferation Treaty, in letter and spirit, with the goal of a complete prohibition of these weapons.

In 2014, at the Third International Conference on the Humanitarian Impacts of Nuclear Weapons Pope Francis’s statement, including this passage, was read to the assembled delegates:

Nuclear deterrence and the threat of mutually assured destruction cannot be the basis for an ethics of fraternity and peaceful coexistence among peoples and states.

In addition to this statement, the Vatican released a landmark study document suggests that the bomb is profoundly destabilizing as well as immoral:

Rather than providing security, as the defenders of nuclear deterrence contend, reliance on a strategy of nuclear deterrence has created a less secure world. In a multi-polar world, the concept of nuclear deterrence works less as a stabilizing force and more as an incentive for countries to break out of the non-proliferation regime and develop nuclear arsenals on their own.

Reliance on nuclear deterrence, then, in the view of the Catholic Church, is impeding disarmament. Further, the study document posits, “the non-proliferation regime is rooted in inequality” and the NPT’s “grand bargain” is failing due to NWS not upholding their half of the deal, calling into question the entire legitimacy of the global system. Failure at the 2015 NPT Review Conference to achieve consensus on a final text supports this assessment of a weakened global nuclear order.

The Church’s discussion of the value of nuclear weapons for deterrence has evolved at a time when the United States, Russia, China, India and Pakistan nuclear are engaged in significant strategic modernization programs. The contradictions between the Church’s teachings and the pursuit of more sophisticated means to deliver nuclear weapons will only grow in the years ahead. The Church’s calls for total disarmament will continue, beginning with Francis’s World Peace Day address on January 1st and another address a few weeks later to the Vatican diplomatic corps.


  1. David (History)

    The Church teaching on Just War would reject the use of Nuclear weapons. The principle of Double Effect (which holds that a bad effect can be tolerated in achieving a good end) only applies when the bad effect is not deliberately intended, would be avoided if possible and does not outweigh the good effect.

    Since the bad effect—the mass indiscriminate killing of civilians—outweighs the good effect, and is often directly intended (the White Paper on the decision to drop the bomb indicated affecting civilians was directly intended), it seems that Nuclear weapons are not compatible with a Just War.

    (If memory serves, the Vatican spoke against the atomic bombs dropped on Hiroshima and Nagasaki).

    Hope this helps

  2. Jonah Speaks (History)

    Thank you for explaining the main points of the Church’s analysis of nuclear war. Shorn of its religious garb, calls for peace, etc., the 1983 Bishops’ letter provides the following conclusions about nuclear policy and strategy:
    1) Nuclear weapons should never be used first, even in a limited manner, and not as an alternative to losing a conventional war. Hence, NATO should take steps to end its reliance on nuclear weapons to deter Soviet conventional attack.
    2) Limited nuclear weapons use is unlikely to remain limited in scale or scope. Plans and weapons for nuclear war-fighting involving multiple exchanges of nuclear weapons are not acceptable. Only plans and weapons for nuclear sufficiency adequate to deter a nuclear attack are acceptable.
    3) Nuclear deterrence against a first strike is acceptable, but any nuclear retaliation must be limited in scope to military targets that are not in or near cities, and must not cause large civilian casualties, even indirectly. Nuclear deterrence is only conditionally acceptable, pending rapid progress on nuclear disarmament.
    I agree with the first two points, basically for the reasons the bishops gave. The third point is more problematic. The 1983 letter says we can never bomb the enemy’s cities, even if the enemy has bombed our cities. This ostensibly “moral” advice is not merely useless, it is quite harmful.
    An unfortunate potential of the nuclear age is that an enemy really could bomb all our cities within the hour. So long as this potential exists, the threat of nuclear retaliation (including the possible bombing of cities) is needed to deter or forestall nuclear war for as long as possible. I heartily endorse rapid global nuclear disarmament, but regardless of whether progress is rapid, slow, or not at all, nuclear deterrence remains a necessary evil so long as nuclear weapons still exist and might be used.

  3. Jonah Speaks (History)

    In addition to nuclear deterrence or war fighting on the one hand, and disarmament or arms control on the other hand, there exist alternative procedures that can serve as a less costly substitute for nuclear war. One alternative has the humanitarian advantage of not requiring the destruction of people, property, or environment. This alternative to detonating nuclear weapons is to order evacuations of cities or other target areas.

    In the event two nuclear armed nations are at war, each nation could order evacuations in the other’s territory. Adequate time (at least two to four weeks) would be allowed for evacuations. If the evacuations were performed as ordered, there would be no nuclear bombings. These evacuations can be continued for as long as needed to obtain a ceasefire or other peace agreement. Evacuations are costly and inconvenient for both sides, but are preferable to the alternative of nuclear war.