Pope Leo XIV issued a Message for the 2026 World Day of Peace addressing rising global conflict and rearmament. The Pope advocates for an "unarmed and disarming" peace, rejecting deterrence based on military force, including nuclear deterrence. He emphasizes that true Christian peace is active and transformative, rooted in moral clarity and the refusal of violence. Pope Leo XIV identifies fear as a central element driving international relations toward conflict, where war is perceived as inevitable. The path to lasting peace requires disarmament, dialogue, and a conversion of hearts.
3 months ago
Pope Leo XIV released his first Message for the World Day of Peace on December 18, 2025, titled “Peace Be with You All: Towards an Unarmed and Disarming Peace.”1 2 3 The document, for the January 1, 2026 observance, echoes his election greeting and centers on Christ's resurrection greeting as transformative.1 2 It proposes peace through moral clarity, dialogue, and heart conversion amid global fear and war threats.1 3
Global military spending surged 9.4% in 2024 to $2.718 trillion, or 2.5% of GDP, fueling rearmament over human development.1 2 3 Pope Leo critiques nuclear deterrence as fear-based irrationality, eroding law, justice, and trust.1 2 Confrontational politics normalizes war preparation, viewing disarmament as naive.1 3
Artificial intelligence and autonomous weapons worsen conflicts by delegating life-and-death decisions to machines.2 3 6 This "destructive betrayal" of humanism is driven by private economic interests, shirking leader responsibility.2 6 Educational shifts promote threat perceptions, neglecting war's millions of victims.2 3
The Pope roots peace in Jesus' unarmed struggle, urging "put your sword back" and recognizing past Christian violence complicity.1 2 Disarmament must start inwardly, converting hearts from suspicion to trust, beyond equal armaments.1 6 Goodness, like God's incarnation as a child, is inherently disarming.1 3
Religions must reject faith's weaponization for nationalism or violence, becoming "houses of peace" via dialogue.1 2 3 Believers refute blasphemy through life witness, prayer, and interfaith encounters.2 3 6 Leaders should prioritize diplomacy, treaties, and supranational institutions over violations.1 6
Peace must be lived, cultivated, and protected like a small flame, countering aggression in daily life.1 3 Cardinal Czerny emphasizes personal hope against war logic, applying to all including soldiers.3 6 Victims like Fr. Pero Miličević and Maria Agnese Moro advocate forgiveness, mutual listening restores humanity.6
Pope Leo counters fatalism, noting peace exists and dwells within, urging Jubilee-inspired disarmament of heart and mind.1 3 Even in rubble, goodness prevails; believers sow peace by believing it possible.3 6 The message invites global pilgrimage toward trust-based relations.1 6
Examine the Catholic doctrine of “unarmed peace” versus military deterrence
The Catholic Church consistently teaches that peace is the highest good, rooted in the Gospel and the dignity of every person made in God's image. Recent papal teaching, particularly under Popes Francis and Leo XIV, promotes an "unarmed and disarming peace"—an active pursuit of reconciliation that rejects violence as a first resort and critiques reliance on military deterrence, especially nuclear arsenals. This vision builds on the just war tradition from Augustine and Aquinas, which permits defensive force only under strict conditions, but recent documents emphasize nonviolence, dialogue, and the rule of law as superior paths. While deterrence is not outright condemned in all forms, it is portrayed as unstable, fear-based, and morally insufficient compared to hearts "disarmed" by charity and forgiveness .
Pope Leo XIV, in his address to ambassadors on December 6, 2025, explicitly calls for an "unarmed and disarming peace", echoing Christ's greeting "Peace be with you" (Jn 20:19). He describes peace not as mere absence of conflict but as "an active and demanding gift, built in the heart and from the heart", requiring renunciation of pride, vindictiveness, and weaponized words. This aligns with Pope Francis's 2017 World Day of Peace message, which proposes nonviolence as a style of politics for peace. Francis urges cultivating nonviolence in personal thoughts, societal relations, and international life, highlighting victims who resist retaliation as the most credible peacemakers.
Pope Francis further develops this in his message for the 2025 World Day of Peace, envisioning a peace granted to "hearts disarmed"—free from selfishness, open to forgiveness, and hopeful in others as resources for a better world. These teachings frame unarmed peace as a proactive ethic, drawing from the Jubilee Year of Hope's call to trust in interpersonal and international relations while promoting human dignity and creation.
Catholic doctrine has long balanced the peace ideal with realism about sin and evil, as articulated in the just war theory originating with St. Augustine and systematized by St. Thomas Aquinas. Augustine viewed war through a theology of sin and providential judgment, where force responds to human fallenness within history's unfolding divine justice. Aquinas summarized just war as requiring legitimate authority, just cause, and right intention to achieve peace, incorporating necessity, proportionality, and discrimination. Just cause traditionally included defense against attack, restitution of property, and punishment of grave injustice, distinguishing defensive from offensive wars.
This framework presumes war as a tragic necessity, not a preference: "war is the negation of all rights and a dramatic assault on the environment", per Fratelli Tutti. St. John XXIII echoed this, stating it "no longer makes sense to maintain that war is a fit instrument with which to repair the violation of justice". The tradition demands morally formed agents, emphasizing order, justice, and peace over vengeance .
Recent teachings sharply question military deterrence, particularly nuclear, as incompatible with unarmed peace. In Fratelli Tutti, Pope Francis argues that "rules by themselves will not suffice if we continue to think that the solution to current problems is deterrence through fear or the threat of nuclear, chemical or biological weapons". He highlights nuclear deterrence's inadequacy against modern threats like terrorism, cybersecurity, poverty, and environmental crises, noting its "catastrophic humanitarian and environmental consequences" and instability based on fear rather than trust.
This echoes broader calls for the "total elimination of nuclear weapons" as a moral imperative, redirecting military spending to a global fund against hunger. Deterrence undermines the universal common good, favoring partisan interests over transparent international law like the UN Charter. Popes Francis and Leo XIV thus present deterrence as a false security that perpetuates anxiety, contrasting it with dialogue, negotiation, and hearts turned to God .
No strict discontinuity exists between just war teaching and unarmed peace; rather, contemporary popes develop the tradition by restricting just cause primarily to defense and prioritizing nonviolent alternatives. Aquinas's criteria—aimed at peace—align with Leo XIV's disarming vision, as both reject war for aggrandizement . Yet, deterrence raises prudential concerns: while classical theory might tolerate limited defensive postures, nuclear threats violate proportionality and right intention by risking indiscriminate annihilation .
The Church urges tireless recourse to negotiation, mediation, and arbitration, seeing nonviolence not as pacifism but as a higher politics. Where sources diverge—classical allowances for offensive elements versus modern defensive restriction—recent magisterium takes precedence, emphasizing forgiveness over retaliation.
In summary, Catholic doctrine elevates unarmed peace as the Gospel imperative, critiquing military deterrence as fear-driven and insufficient, while retaining just war as a grave last resort. This calls believers to personal and political nonviolence, trusting in God's peace amid a fallen world .