Cardinal Tobin: War and Peace
Click a button to jump to the section:
Vol. 7. No. 25
In so far as we are sinners, the threat of war hangs over us and will so continue until Christ comes again; but insofar as we can vanquish sin by coming together in charity, violence itself will be vanquished (cf. GS 78 § 6)
Dear Sisters and Brothers in Christ,
War is the result of sin. It is the destruction of the harmony and moral order that God intended to exist among individuals, nations, and peoples. War is always evil even when it is undertaken out of necessity for the defense of humanity. The Church opposes all war, and it stands in favor of peace—always and everywhere.
Yes, there are times when war is unavoidable—precisely in order to protect human lives or to restore peace. But war is never welcome. It is always reprehensible because of the damage it inflicts on human life (especially the innocent) and property (especially homes, businesses, hospitals, schools, and places of worship). “War is hell” is not just a slogan. It is a fitting description of the horrors and chaos that result from the acts of war, especially in this nuclear age.
The Church’s Just War Doctrine is a helpful tool in determining whether or not war is justified under very strict and limited conditions. But as Pope Leo XIV has pointed out (see selection below), this teaching may need to be examined, and possibly updated, to ensure that it takes into account the evolving circumstances of modern life and contemporary warfare. For example, the use of unmanned drones powered by artificial intelligence (AI) raises serious questions about moral responsibility that need to be addressed as never before.
When the Church says that it always stands for peace over and against war, we are describing a state of human affairs that is much greater than simply the absence of armed conflict. Peace is not just social stability. Our understanding of peace is ordered toward communion with God and the true good of the human person. The Church’s teaching on peacemaking says that Jesus’ shalom means “perfect communion with God,” and that peacemaking flows from humility, gentleness, forgiveness, and mercy.
Belligerence and warmongering are the opposite of peacemaking. That’s one reason Pope Leo insists that we stop romanticizing the act of war and its symbolic activities. War is not glorious, and while we are right to honor the heroism of those who have fought against tyranny and injustice, we should never pretend that the acts of war are themselves worthy of celebration.
True peace demands that we surrender egoism, false pride, and vengeance. It asks us to be gentle, humble, and forgiving even when everything in us cries out for strict justice or revenge against those who have insulted or injured us. Jesus teaches us the counter-intuitive truth that love overcomes all evil, whereas aggressive action simply causes further enmity.
The holy women and men who formulated what we now call the Just War Doctrine were peacemakers after the Sacred Heart of Jesus. They recognized the regrettable need for defensive action against the powers of darkness who would destroy everything we hold dear, but they were adamant that war is evil and that peace demands remarkable restraint and forgiveness. So, for example, when Pope Leo asks us to stop fighting and engage in serious dialogue to find solutions that will make peace a reality, he is not being naïve. He is standing with Jesus, and all the saints, in the effort to build the kingdom of peace here and now.
The Second Vatican Council taught that “The arms race is one of the greatest curses on the human race and the harm it inflicts on the poor is more than can be endured” (GS 81 § 3). Pope Leo affirms this teaching, and he invites all people of good will to embrace the vision of peace offered by the Prophet Isaiah:
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 anymore (cf. Is 2:4).
The Church’s responsibility—always and everywhere—is to advocate for justice, charity, and lasting peace. We deeply regret the sinful human condition that has made war so prevalent in human history to the present day. Rather than celebrating war, we look for ways to rejoice in the art of peacemaking, and we honor those heroes among us who have sacrificed so much to effect, preserve, and defend the virtues that make peace possible.
May our Lord Jesus Christ, the Prince of Peace, inspire all of us to work for justice with charity and to pray for a peace that will endure until He comes again.
Sincerely yours in Christ the Redeemer,
Cardinal Joseph W. Tobin, C.Ss.R.,
Archbishop of Newark
June 26, 2026
The session, entitled “The Culture of Power and the Civilization of Love,” was devoted to reflection on Chapter Five of the encyclical Magnifica Humanitas.
War must not be normalized
Eleven groups addressed the challenges of the present time, highlighting “the dehumanizing force of the culture of power, its universal reach, the temptation to conform to the logic of the powerful, and the normalization of war and polarization, which lower society’s tolerance for violence and encourage dangerously simplistic approaches to resolving conflicts”.
Against this backdrop, the participants stressed the responsibility to build peace and a civilization of love. They also emphasized the importance of offering a credible witness—beginning within the Church itself—through a language centered on people: one of listening, forgiveness, reconciliation, restorative justice, and concrete gestures. Such a language, they said, is capable of touching the hearts of those caught up in conflict, acknowledging the wounds caused by war, and fostering the search for unity within the Church.
The responsibility to build peace
The discussion also underscored that unity within the Church is essential to its credibility, as is dialogue with other faiths and religions, particularly Islam. At a time when the globalization of indifference makes people increasingly insensitive to the suffering of others, every individual is called to take responsibility for building peace.
In this context, all the groups reaffirmed the centrality of faith in Christ and of the Gospel, which has the power to transform the world when it is lived rather than treated as mere theory. They also highlighted the Church’s original vocation, noting that some situations can only be addressed through God’s intervention. Several groups pointed to the Church’s work in the Holy Land and Eastern Europe as examples.
The discussion also addressed the role of political authority, calling for it to be freed from what was described as its toxic link with economic power. Other topics included the family, education, the difficulty of moving beyond the demand for immediate solutions, and the need for bold evangelization. Several groups also highlighted the role of the Holy See’s diplomacy and of papal nuncios in ensuring that the Church’s voice continues to be heard.
Standing with a papal appeal for peace
Within this context, many participants stressed the need to move beyond the logic of just war, since the Gospel cannot be imposed by force, and instead to speak of the right to proportionate self-defense.
Deep gratitude was expressed to Pope Leo for the encyclical, for his condemnation of armed conflicts, and for his repeated appeals for peace. The discussion also reflected on the Petrine ministry (munus petrinum) as a guarantee of the Church’s independence from political authority, as well as on the need for symbolic gestures that can serve as visible signs of peace in the present time.
(A selection from the Vatican News report on the afternoon session of the Extraordinary Consistory, held on June 26, 2026, in the Vatican’s Paul VI Audience Hall.)
A Message from Pope Leo XIV: In the One Christ, We are One
The culture of power
188. In our time, a culture of power is taking hold, in which the availability of resources and the ability to dominate tend to dictate the agenda and criteria for decision-making. In this way, the common good of humanity is relegated to the background and the concrete tragedy of peoples at war is reduced to a secondary consideration in relation to strategic interests. This culture of power infiltrates society, changes relationships and behaviors, and grows by normalizing war, pursuing ever-greater military power, taking advantage of the crisis of multilateralism and fueling a false realism that insists that there is no alternative.
The normalization of war
189. In 1965, the words of Saint Paul VI resounded powerfully at the UN General Assembly: “Never again war, never again war!” We must acknowledge that, despite the desires and declarations for peace, the past sixty years have been marked by conflicts of astonishing brutality, often affecting civilian populations on a massive scale, leading to the death of innocent victims, mass displacement, social destabilization and long-lasting wounds. Nevertheless, in public discourse, there was a widespread conviction that war should remain a last resort, subject to strict ethical and legal limits, and always oriented toward a political vision of peace. Following developments in the immediate post-First World War period, a turning point occurred after the Second World War: peace was made the focus of the international order, as attested in particular by the United Nations Charter, with the intention to “save succeeding generations from the scourge of war.” Likewise, many national constitutions restricted the use of force to extreme and strictly limited circumstances. Even during the Cold War, despite the existence of serious conflicts, there remained the awareness that a new world war had to be avoided at all costs.
190. Today, however, we are witnessing a real paradigm shift in public discourse and in decisions regarding rearmament, with a troubling revival of war as an instrument of international politics, while the very ethical principles that had previously limited its use are being eroded. Regional conflicts that drag on over time, escalating tensions and reciprocal threats are becoming almost commonplace, and forms of conflict driven by the desire for territorial expansion that were thought to be overcome are re-emerging. Public opinion is gradually being shaped and conditioned by polarizing media narratives, which are often amplified by algorithms that prioritize conflict and confrontation.
191. We are also witnessing a disconcerting loss of historical memory, as first-hand accounts of the Holocaust and the two World Wars are disappearing. This leads to a selective or distorted rewriting of the past, in a context where fake news and the manipulation of narratives obscure the lessons that have been learned. Without a living memory of the horrors of war, political decisions risk being made on the basis of power alone, without any consideration for the long-term consequences.
192. To all of this, the media and digital dimensions are adding new and decisive elements. Communication networks, fragmented information environments and algorithms that reward conflict can magnify polarization and resentment, increase propaganda and make shared discernment more difficult. Thus, war is not only fought, but also culturally conditioned through simplistic narratives, a friend-or-foe mentality, disinformation and fear. When historical memory fades and the ethical principles that protect civilians and the most vulnerable are weakened, it becomes easier to justify violence as necessary, inevitable or even “sanitized.” It is in this context that humanity is slipping into a violent culture of power, where peace no longer appears as a responsibility to be taken on, but as a fragile interval between conflicts. Today, more than ever, without prejudice to the right to self-defense in the strictest sense, it is important to reaffirm that the “just war” theory, which has all too often been used to justify any kind of war, is now outdated. Humanity possesses far more effective and capable tools for promoting human life and resolving conflicts, such as dialogue, diplomacy and forgiveness. The use of force, violence and weapons reflects a relational poverty that always has disastrous consequences for civilian populations.
Force without limits
193. The growth of the military-industrial complex has become a defining feature of the current political landscape and has become a key sector in the economy of various countries. The close link between economic interests, the military apparatus and political decisions produces an “armed nation,” in which war appears as a natural extension of politics, and the arms market becomes an autonomous driving force behind military decisions. Nor can we ignore the enormous economic interests behind war. The armaments industry, and countries that supply weapons, profit from a market that thrives precisely on conflicts. In this sense, there are also financial interests that contribute to fueling tensions in various regions of the world.
194. Military arsenals are receiving renewed attention. In the past, recognition of the threat posed by weapons capable of destroying all of humanity had promoted paths toward détente and disarmament negotiations. Unfortunately, this approach has been left behind, and the evolution of nuclear arsenals — including the prospect of its “tactical” use — makes the use of such weapons seem less improbable. In this context, the Treaty on the Prohibition of Nuclear Weapons, which came into force in 2021 with the support of over seventy countries, is an important step. However, it risks remaining largely symbolic since the major nuclear powers have not agreed to it. This has led to the widespread yet erroneous belief that nuclear deterrence is an indispensable prerequisite for security. This has also contributed to a new arms race, which is hard to control and accompanied by the gradual dismantling of nuclear reduction agreements, as well as the development of “miniaturized” weapons, that make their use seem like a more viable option.
195. The same logic applies to conventional warfare. Military force, weak diplomatic initiatives and the complexity of the interests at stake contribute to conflicts that tend to become protracted, with extremely high human and environmental costs. It is much easier to start a war than to stop it, and yet, discussion on conflict prevention remains tragically marginal.
196. The situation is further destabilized by the presence of new armed operatives, such as jihadist groups, private militias and criminal networks that mark the end of the State’s monopoly on the use of force. Often these groups intertwine vague ideological motivations with concrete economic interests, transforming war into a “way of life” for entire generations of young people and children. Here, the objective is no longer a definitive victory, but the perpetuation of conflict as a source of power and income.
Weapons and artificial intelligence
197. The above-mentioned scenario is linked to the unceasing development of weapons systems, particularly those involving AI. The Holy See has recently observed that the growing ease with which autonomous weapons systems can be deployed makes war more “feasible” and less subject to human control. This violates the principle that armed force should be used only as a last resort in cases of legitimate self-defense. For this reason, the development and use of AI in warfare must be subject to the most rigorous ethical constraints, to guarantee respect for human dignity and the sanctity of life and to avoid a race to develop such arms.
198. Sometimes there is talk of “artificial moral agents,” as if machines were able to distinguish between right and wrong with greater consistency than a human being. Yet moral judgment cannot be reduced to calculation, for it involves conscience, personal responsibility and the recognition of the other as a person. Therefore, it is not permissible to entrust lethal or otherwise irreversible decisions to artificial systems. No algorithm can make war morally acceptable. AI does not remove the intrinsic inhumanity of conflict; indeed it can only bring about conflict more quickly and render it more impersonal, lowering the threshold for resorting to violence, transforming defense into threat prediction and thus reducing victims to data. In this way, it will accustom us to the idea that violence is inevitable and needs only to be optimized. This does not diminish the importance of instilling, as far as possible, values and sound judgment into the artificial systems we build, so that they can contribute to a moral ecosystem in which humans are better able to listen to their own consciences, as well as allowing AI models to establish appropriate boundaries.
199. It is not enough to invoke a generic type of ethics. Concrete criteria for discernment must be established. The first such criterion concerns personal responsibility. When a decision to strike becomes automated or opaque, the risk of abdicating responsibility increases. For this reason, the chain of responsibility must be identifiable and verifiable; those who design, train, authorize and employ technology must be held accountable for their decisions. The second criterion pertains to the moral timeframe for making judgments. While AI tends to expedite the decision-making processes, speed and efficiency should never be the supreme motivating force for the irreversible decisions made in the context of war. The third criterion is the identification and protection of civilians. Any technology that facilitates attacks without seeing the face of human beings lowers the moral threshold of conflict. Target selection and the use of force must not confuse combatants and non-combatants, nor ignore the impact on defenseless populations.
200. These criteria give rise to certain non-negotiable requirements. First, all systems used in a war setting must guarantee the possibility of retracing and reconstructing decision-making processes, so that accountability and blame are not collapsed into “the machine.” Second, the decision to use lethal force cannot be delegated to opaque or automated processes, but must remain under effective, self-aware and responsible human control. Finally, it is imperative to establish a shared framework — also at the international level — in order to curb the technological arms race and ensure robust protection for civilians and the infrastructures necessary for their survival.
(Selected from the encyclical of Pope Leo XIV, Magnifica Humanitas, no. 188–200)
My Prayer for You
Shalom aleichem lekulam! (Peace be with you all!)
Lord Jesus Christ, your familiar greeting, Shalom, invites us to enter into perfect communion with our Triune God. Grant us your peace, O Lord. Help us to work for justice, to practice charity, and to pray that all our sisters and brothers will be united in pursuit of the common good of all.
Amen.