The arms race

The arms race is not the mere fact of possessing weapons. Every State has the right and duty to ensure its legitimate defense, and therefore to possess means proportionate to its security. What the expression names is a dynamic: the indefinite, reciprocal and competitive growth of arsenals, in which every advance by one side justifies the over-armament of the other.

A spiral that feeds on itself

The driving force of the arms race is mutual fear. The nation that arms itself claims to be doing so for defense; but its neighbor perceives this armament as a threat and arms in turn; the first, seeing the other arm itself, feels confirmed in its fear and accelerates further. It is a spiral with no natural summit: no level of armament is ever "enough", because security is always measured relative to the other. John XXIII had already described this mechanism in Pacem in Terris: armaments are commonly justified by saying that peace can be ensured only by a balance of armed forces, but "if one country increases its military strength, others are immediately aroused by a competitive spirit to augment their own supply of armaments"^[3].

This dynamic has a cost measured not only in risk of war, but in swallowed-up resources. The sums spent on "the production of ever new weapons" are so many riches taken away from the real needs of peoples — a point on which the whole social Magisterium will insist, from Pius XII to Francis.

The "balance of terror" and deterrence

The classic justification for the arms race is deterrence: weapons — especially the most terrible ones — are accumulated not in order to use them, but to discourage an adversary from attacking by the prospect of unbearable reprisals. During the Cold War, this logic received a famous name: the "balance of terror", in which two nuclear blocs held each other in check by the certainty of mutual destruction.

The Catechism recognizes the sincerity of this intention — many see it as "the most effective way of ensuring peace among nations" — but immediately subjects it to severe judgment:

"The accumulation of arms strikes many as a paradoxically suitable way of deterring potential adversaries from war. [...] This method of deterrence gives rise to strong moral reservations. The arms race does not ensure peace. Far from eliminating the causes of war, it risks aggravating them." — Catechism of the Catholic Church, § 2315^[4]

The expression "balance of terror" already states the ambiguity: it is a balance, therefore a kind of apparent order; but it is a balance of terror, founded on the reciprocal threat of annihilation. For the Church, a peace that holds only through fear is not the "tranquillity of order" that true peace is: it is, at best, suspended war.

A question of social doctrine, not only strategy

One might think that the arms race belongs only to defense specialists. The Church says the opposite: because it involves the life of peoples, the use of goods, and the international order, it fully belongs to social doctrine. The Catechism underlines this by recalling that "the production and the sale of arms affect the common good of nations and of the international community", and that public authorities therefore "have the right and duty to regulate them"^[5].

The arms race thus intersects several permanent principles of social doctrine: the common good (which it compromises), the universal destination of goods (which it violates by diverting resources), solidarity between nations (which it replaces with distrust), and peace itself (which it claims to serve but undermines). This is why the social Magisterium treated it as one of its major twentieth-century themes.

The reference text is number 81 of the pastoral constitution Gaudium et Spes (1965), entitled precisely "The arms race". In the middle of the Cold War, under the shadow of the nuclear threat, the Council issued a judgment of unusual firmness.

The context: Vatican II facing the bomb

Gaudium et Spes was promulgated on 7 December 1965, twenty years after Hiroshima and Nagasaki, at the heart of the confrontation between the two blocs. The Council did not hide behind generalities: it looked directly at weapons of mass destruction and the accumulation of arsenals. Number 80 first condemns "total war" — "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"^[6]. Number 81 then examines the armed peace that claims to ward off such war.

Why the arms race does not bring peace

The Council concedes the motive: many regard the balance of forces as the surest means of deterring war. But it rejects that confidence. The arms race, it says, "is not a safe way to preserve a steady peace", and the so-called balance resulting from it "is not really peace nor is it a sure way to preserve peace". Worse still, far from eliminating the causes of war, it "gradually aggravates them"^[7]. The reasoning, later repeated by the Catechism, is twofold: deterrence does not remove the motives for conflict (it freezes them under threat), and over-armament itself becomes a factor of instability: it "multiplies reasons for conflict and increases the danger of escalation"^[8].

The scandal of the poor who are harmed

To this strategic critique, the Council adds a properly social argument, which will be the guiding thread of the whole Magisterium:

"The arms race is one of the greatest curses on the human race and the harm it inflicts upon the poor is more than can be endured." — Second Vatican Council, Gaudium et Spes, no. 81^[9]

The "fabulous sums" spent on preparing new weapons are, at the same time, denied to the present miseries of the world^[10]. The scandal is therefore not only the risk of future death: it is the present theft inflicted on the hungry, the sick, and peoples without schools or hospitals. The arms race already kills, before any shot is fired, by diverting resources that would save lives. This link between armaments and poverty is so essential that the Catechism made it its summary formula on the subject (§ 2329), quoting Gaudium et Spes 81 word for word.

The rejection of the arms race is not an isolated opinion: it is a constant and cumulative teaching of twentieth-century popes, each receiving and specifying the teaching of his predecessors.

Pius XII: fear of atomic war

From the dawn of the nuclear age, Pius XII warned against a war capable of destroying everything. Pacem in Terris would repeat his warning, issued during the Second World War: "It is impossible to prevent a third world war, with its economic and social ruin, its errors and moral disorders, from sweeping over mankind unless effective steps are taken"^[11]. The papacy thus entered, even before the Council, into a critical vigilance toward peace through terror.

John XXIII: Pacem in Terris and mutual trust

The encyclical Pacem in Terris (11 April 1963), published a few months after the Cuban missile crisis, gives the subject its densest formulation. John XXIII explicitly calls for "a cessation to the arms race", through concerted and controlled reduction:

"Justice, right reason, and the recognition of man's dignity cry out insistently for a cessation to the arms race. The stock-piles which exist in various countries must be reduced all round and simultaneously by the parties concerned. Nuclear weapons must be banned. A general agreement must eventually be reached about progressive disarmament and an effective method of control." — Saint John XXIII, Pacem in Terris, no. 112^[12]

Above all, the pope reaches the root: no lasting external disarmament is possible without a disarmament "in men's souls". The very principle on which the arms race rests must be overturned:

"The true and solid peace of nations consists not in equality of arms but in mutual trust alone." — Saint John XXIII, Pacem in Terris, no. 113^[13]

This substitution — from the balance of arms to mutual trust — is the heart of the Catholic position. As long as security rests on threat, the race continues; it can stop only through a moral change founded on trust and justice.

Paul VI: "an intolerable scandal"

Paul VI carried the issue onto the world stage. On 4 October 1965, before the United Nations General Assembly, he uttered his famous cry — "No more one against the other, no more, never again!" — and called the nations to disarm both hands and hearts:

"If you wish to be brothers, let the weapons fall from your hands. One cannot love with offensive weapons in his hands." — Saint Paul VI, address to the UN, 4 October 1965^[14]

Two years later, in Populorum Progressio (1967), he indissolubly linked armaments and development, in a striking formula:

"When so many people are hungry, when so many families suffer misery, [...] every exhausting arms race becomes an intolerable scandal. We must denounce it." — Saint Paul VI, Populorum Progressio, no. 53^[15]

John Paul II: deterrence as a provisional "step"

John Paul II faced the question at the height of the nuclear confrontation. In his message to the Second Special Session of the UN General Assembly devoted to disarmament (7 June 1982), he formulated a nuanced judgment that would remain the reference for two generations: deterrence may be tolerated, but only as a step toward disarmament, never as an acceptable state of affairs.

"In current conditions, deterrence based on balance, certainly not as an end in itself but as a step on the way toward progressive disarmament, may still be judged morally acceptable." — Saint John Paul II, message to the UN on disarmament, 7 June 1982^[16]

This tolerance is conditional and transitory: it is valid only as a path toward disarmament, and collapses if deterrence becomes an end in itself or an alibi for perpetuating the race. After the fall of the Soviet bloc, the pope would in fact denounce retrospectively "a senseless arms race [that] swallowed up the resources needed for the development of national economies and for assistance to the less developed nations"^[17].

Francis: from use to possession

Francis took a decisive step. On 10 November 2017, before an international conference held at the Vatican, he condemned not only the threat or use of nuclear weapons, but their very possession:

"The threat of their use as well as their very possession is to be firmly condemned, precisely because their existence is linked to a logic of fear that affects not only the parties in conflict but the entire human race." — Pope Francis, address on integral disarmament, 10 November 2017^[18]

At Hiroshima, on 24 November 2019, he confirmed and solemnized this judgment: "The use of atomic energy for purposes of war is immoral, just as the possessing of nuclear weapons is immoral"^[19]. At Nagasaki the same day, he denounced "the money spent and the fortunes made through the manufacture, upgrading, maintenance and sale of ever more destructive weapons" as "an affront crying out to heaven"^[20]. In Fratelli Tutti (2020), he finally proposed converting the money spent on weapons into a "global fund" against hunger^[21].

The Catechism of the Catholic Church (1992) condenses this teaching into two paragraphs (§§ 2315-2316), within its section on safeguarding peace.

The accumulation of weapons, a "paradoxical" method

Paragraph 2315 — already quoted above — describes deterrence as a "paradoxically suitable way of deterring potential adversaries from war" and opposes to it four linked objections: the arms race does not ensure peace; it risks aggravating the causes of war; it prevents help from being given to needy populations and impedes the development of peoples; finally, over-armament "multiplies reasons for conflict and increases the danger of escalation"^[22]. None of these objections is secondary, and together they form a complete indictment.

Production and trade in arms: a duty to regulate

Paragraph 2316 shifts the gaze from strategy to economics. The manufacture and trade of weapons are not indifferent private affairs: they "affect the common good of nations", and therefore fall under public authority.

"The short-term pursuit of private or collective interests cannot legitimate undertakings that promote violence and conflict among nations and compromise the international juridical order." — Catechism of the Catholic Church, § 2316^[23]

The arms trade thus involves the destination of goods and the moral responsibility of producers and merchants. Selling weapons to those who "promote violence" is not an economically neutral act: it is cooperation with an evil that "cries out to heaven", in Francis's words.

The Compendium of the Social Doctrine of the Church (Pontifical Council for Justice and Peace, 2004) gathers and systematizes this teaching in its section on disarmament (nos. 508-512).

The principle of sufficiency

The Compendium sets the goal: "general, balanced and controlled disarmament"^[24]. Above all, it states a clear moral criterion, the principle of sufficiency: a State may possess "only those means necessary for its legitimate defense". Any accumulation beyond this threshold, or any generalized trade in arms, "cannot be morally justified". It adds a decisive warning: "arms must never be considered like other goods exchanged on the international or domestic markets"^[25]. A weapon is not an ordinary commodity.

Weapons of mass destruction

For nuclear, biological and chemical weapons, the Compendium speaks of a "particularly grave threat" and places those who possess them responsible "before God and all of humanity". It sets as linked and urgent goals non-proliferation, nuclear disarmament, and the ban on tests, under "effective controls at the international level"^[26].

Anti-personnel mines, small arms, child soldiers

The Compendium then turns to weapons that kill every day. It calls for the ban on anti-personnel mines, "insidiously inhuman" devices because they "continue to cause harm long after the cessation of hostilities"^[27]. It demands control of the production and trafficking of small arms, "those that kill the most and are used most often in non-international conflicts"^[28]. Finally, it denounces as "an intolerable crime" the use of children and adolescents as soldiers^[29]. The arms race is therefore not only the affair of great nuclear powers: it continues in the diffuse trade that feeds forgotten wars.

The case of nuclear weapons deserves particular attention, because this is where the teaching has most visibly progressed in recent decades — not by rupture, but by deepening.

Deterrence tolerated as a "step"

During the Cold War, the Magisterium tolerated nuclear deterrence, but under strict conditions. John Paul II in 1982 said it could be "morally acceptable" only "as a step on the way toward progressive disarmament", and "certainly not as an end in itself"^[30]. Three implicit conditions framed this tolerance: that deterrence truly serve to avoid war, that it remain a transitory means, and that it be accompanied by effective efforts at disarmament. The Compendium would specify that "the policies of nuclear deterrence typical of the Cold War period must be replaced with concrete measures of disarmament based on dialogue and multilateral negotiations"^[31].

Francis's turning point

Francis observes that these conditions are no longer met: deterrence has settled in as a permanent state, arsenals are modernized rather than reduced, and the mere existence of such weapons keeps all humanity under a "logic of fear". He draws the consequence: the very possession of nuclear weapons is now condemned^[32]. This judgment accompanied the adoption, in 2017, of the Treaty on the Prohibition of Nuclear Weapons, which the Holy See was among the first to sign and ratify.

Continuity or rupture?

Should this be seen as a contradiction with John Paul II? No: it is a homogeneous development, within the hermeneutic of continuity. The permanent principle has never changed: deterrence is valid only as a step toward disarmament, never as an end. John Paul II tolerated deterrence because it was believed to be oriented toward disarmament; Francis condemns it because it manifestly no longer is and has hardened into a permanent balance of terror. Since the condition stated in 1982 is no longer fulfilled, the conclusion changes — not the principle. It is the application of the same doctrine to a transformed situation, as the social Magisterium has always done^[33].

The Church's teaching on the arms race raises serious objections, which should not be avoided.

"Would disarmament not hand the weak over to the aggressor?"

The objection is serious: naive disarmament could leave a people defenseless before a tyrant. The Church does not ignore this. She firmly maintains the right of legitimate defense: "As long as the danger of war persists [...] governments cannot be denied the right to legitimate defense, once every means of peaceful settlement has been exhausted", teaches Gaudium et Spes (no. 79)^[34]. The condemnation bears on the race in armaments — indefinite and competitive accumulation — not on the possession of means proportionate to defense. The criterion is the principle of sufficiency of the Compendium: what exceeds legitimate defense and enters the spiral is what is condemned.

"Is unilateral disarmament required?"

No. The Magisterium does not ask one nation to disarm alone while leaving others armed: it calls for "general, balanced and controlled" disarmament, "by common agreement and with effective controls"^[35]. Catholic disarmament is concerted, reciprocal and verifiable — not a moral capitulation, but a common work of trust. It is precisely this mutual character that answers the previous objection: no one is asked to expose himself alone.

Christian realism against false peace

The Church is neither bellicist nor pacifist in the sense of an unarmed and angelic disarmament. She rejects two false peaces: that of the balance of terror, which is only suspended war, and that of a pacifism that would deliver the innocent to the aggressor. Her way is demanding: to build real peace through justice, mutual trust, international law and concerted disarmament. This is more difficult than accumulating weapons — but it is the only peace worthy of the name.

Social doctrine does not stop at treaties. John XXIII had said it: external disarmament will remain "almost impossible" without a disarmament "in men's souls"^[36]. The arms race has an inner root: fear, mistrust, the pride of nations, the greed of merchants. Arsenals cannot be durably disarmed unless these passions are disarmed.

Isaiah's prophecy: from swords to plowshares

Biblical hope gives this disarmament its definitive image — that of a world where instruments of death become instruments of life:

"They shall beat their swords into plowshares, and their spears into pruning hooks. Nation shall not lift up sword against nation, neither shall they learn war any more." — Isaiah 2:4 (repeated in Micah 4:3)^[37]

This messianic prophecy is not a political utopia: it is the fruit of the reign of God, where peace comes from the conversion of hearts and restored justice. It inspires the statue Let Us Beat Swords into Plowshares offered to the United Nations, but it first states a spiritual truth: true peace is not a balance of forces; it is a gift to receive and a work of conversion.

Peace, fruit of justice and charity

The arms race is, in the end, the symptom of a lack of peace within and among peoples — a lack of justice, a lack of solidarity, a lack of trust. This is why the Church never separates the question of weapons from that of development: "development is the new name for peace", said Paul VI. As long as nations live in injustice and fear, they will arm themselves; the true road to disarmament passes through justice, sharing and fraternity.

Disarming self-love: the light of the Divine Will

The spirituality of the Divine Will transmitted to Luisa Piccarreta (1865-1947) sheds light on this inner root. Exterior war is born from the intimate war of the human will against the Will of God; the peace of the world presupposes that souls restore to God his reign within them. The person who lives in the divine Fiat lays down his own "weapons" — self-love, self-assertion, mistrust — so that God's Will of peace may reign, and calls this reign upon all creation^[38]. The deepest disarmament begins there: in the heart that ceases to make war on God.

• Peace — the positive value that the arms race claims to serve and in fact undermines.
• Just war — the framework of the right of legitimate defense, which distinguishes proportionate armament from the arms race.
• The universal destination of goods — the background of the "scandal" of resources diverted from the poor.
• The common good — which "the production and trade of arms" directly affects (CCC 2316).
• Solidarity — Opus solidaritatis pax: peace as the fruit of solidarity among nations.
• Globalization — the framework of interdependence in which the arms trade now operates.
• Totalitarianism — the regime that turns armaments into an instrument of domination.