The just war viewpoint associated with Augustine of Hippo (354-430 AD) holds that war, while inherently sorrowful and a consequence of sin, can be morally permissible - and sometimes obligatory - when waged under specific conditions. Advocates of this position hold that Augustine laid the foundational framework for Christian just war theory, reconciling Roman civic duty with Christian ethics and establishing criteria that shaped Western moral and legal thinking about armed conflict for over fifteen centuries. This viewpoint is held primarily by Christian theologians, Catholic moral philosophers, military ethicists, and scholars of political philosophy working within the Western tradition.

Augustine's just war position rests on a theological anthropology that takes human sinfulness seriously. Advocates hold that Augustine rejected both the pacifist reading of the Sermon on the Mount and the Roman glorification of martial virtue, arguing instead that war is a tragic necessity in a fallen world. Peace is the highest good and the proper end of all human striving, but in a world disordered by sin, the refusal to use force against injustice is itself a moral failure - an abandonment of one's neighbor to harm.

This is grounded in Augustine's distinction between the City of God and the City of Man. The earthly city cannot achieve true peace, only a provisional, imperfect order. War, on this view, is an instrument for preserving that imperfect order against greater disorder.

Augustine's framework requires that war be fought for a just cause. Proponents hold that Augustine identified several legitimate grounds, including:

• Defense against unprovoked aggression
• Recovery of wrongfully seized property or territory
• Punishment of a nation or people that has committed grave injustice and refused to make restitution

Augustine drew on Cicero's earlier formulation but gave it theological grounding. He held that aggressive war - war waged for conquest, glory, or material gain - is always sinful. The cause must be remedial: correcting a wrong, not pursuing advantage.

A just war, for Augustine, must be declared and waged by legitimate public authority - not by private individuals, factions, or mercenaries acting on their own initiative. Advocates note that Augustine held soldiers acting under lawful orders to be morally shielded even when the justice of the war itself was uncertain, provided they had no reason to believe the cause was clearly unjust. The responsibility for an unjust war falls on the authority that commands it, not the soldier who obeys in good faith.

Augustine placed unusual emphasis on the interior disposition of those who wage war. The just warrior, on this view, must be motivated by love - including love of the enemy. Violence is permitted not from hatred, revenge, or desire for domination, but from the necessity of restraining evil and protecting the innocent. Augustine held that a man could kill in battle without sinning if he acted without malice and from duty.

This interior criterion is regarded by advocates as Augustine's most distinctively Christian contribution to just war theory, distinguishing it sharply from classical Roman accounts of honorable war.

Advocates emphasize that Augustine held peace - not victory - to be the proper end of just war. War is never to be waged for its own sake or for national aggrandizement. The belligerent must seek to restore a just and stable peace, ideally one that includes the defeated party. Augustine's famous formulation is that even wars must be waged “with a disposition for peace.”

Augustine developed his just war thinking primarily in response to two pressures: the Roman Empire's increasing reliance on Christian soldiers and officials, and the theological challenge posed by pacifist readings of Christian scripture.

Early Christian communities had been divided on whether believers could serve in the Roman military. By Augustine's time, the Empire was Christian in name, and the question had become unavoidable. Augustine engaged extensively with the Donatist controversy and the Manichean heresy, both of which shaped his understanding of coercion, authority, and conscience.

His most systematic treatment appears in Contra Faustum Manichaeum (c. 397-398 AD) and Quaestiones in Heptateuchum (c. 419 AD), as well as in scattered passages of The City of God (413-426 AD) and his correspondence, particularly letters to the Roman military commander Boniface and to Marcellinus.

Augustine drew heavily on Cicero's De Re Publica and De Officiis, recasting the Roman tradition of bellum iustum within a Christian moral framework. He also engaged the Old Testament accounts of divinely commanded warfare, holding that the Israelite wars of conquest were just because directly commanded by God - a special case he did not extend to ordinary human rulers.

His framework was systematized and extended by Thomas Aquinas in the Summa Theologiae (II-II, Q. 40), who formalized Augustine's scattered observations into the three classic criteria: just cause, right authority, and right intention. Subsequent development by Francisco de Vitoria, Francisco Suárez, and Hugo Grotius built the tradition into international law.

• Augustine of Hippo (354-430 AD) - Bishop of Hippo Regius in Roman North Africa; author of The City of God, Confessions, and extensive correspondence; the originating thinker of this framework within Christian theology.
• Thomas Aquinas (1225-1274) - Dominican friar and scholastic theologian; systematized Augustine's criteria in the Summa Theologiae and made Augustine's just war framework the standard Catholic position.
• Francisco de Vitoria (c. 1483-1546) - Spanish Dominican theologian; extended Augustine-Thomistic just war doctrine to questions of conquest and the rights of indigenous peoples in the New World.
• Paul Ramsey (1913-1988) - American Protestant ethicist; revived Augustinian just war thinking in the twentieth century, applying it to nuclear deterrence and modern warfare in works such as War and the Christian Conscience (1961) and The Just War (1968).
• Jean Bethke Elshtain (1941-2013) - American political philosopher; authored Augustine and the Limits of Politics (1995) and Just War Against Terror (2003), arguing for the contemporary relevance of the Augustinian framework.
• James Turner Johnson - American historian of ethics; has traced the development of just war tradition from Augustine through modernity in Just War Tradition and the Restraint of War (1981) and related works.

Advocates disagree over whether Augustine's requirement of legitimate authority is satisfied only by sovereign states, or whether it can extend to non-state actors, revolutionary movements, or supranational bodies such as the United Nations. Some Augustinian thinkers hold that only recognized sovereign governments can wage just war; others allow for broader application.

Augustine's criteria address response to actual aggression or demonstrable injustice. Advocates disagree sharply over whether the Augustinian framework permits preemptive strikes against gathering threats, or whether it requires that harm be imminent and actual. This debate intensified after the 2003 Iraq War.

Augustine's own writing did not develop a detailed account of noncombatant immunity, though his insistence on right intention implies limits on targeting civilians. Later just war thinkers derived the principle of discrimination - the prohibition on deliberately killing non-combatants - from Augustinian foundations, but the derivation is contested. Some hold it was implicit in Augustine; others regard it as a genuinely later addition to the tradition.

A minority tradition within Christianity, represented by figures such as John Howard Yoder and the Mennonite and Quaker traditions, holds that Augustine's accommodation of violence fundamentally distorted Christian ethics and that the Sermon on the Mount requires unconditional nonviolence. Advocates of the Augustinian position respond that this reading is insufficiently attentive to neighbor-love and the duties of those who hold public office.

Twentieth and twenty-first century advocates have debated extensively whether modern weapons - including aerial bombardment, nuclear deterrence, and drone strikes - can satisfy Augustinian proportionality requirements. Paul Ramsey and others have argued for a strong reading of noncombatant immunity that rules out weapons of mass destruction; others hold that deterrence and collateral damage can be justified under the double-effect principle derived from the tradition.

• Augustine of Hippo
• Just War Theory
• Just War Theory - Debate
• Christian Pacifism Viewpoint
• Thomas Aquinas - Just War Viewpoint
• Just War Theory - History

1. Augustine of Hippo, Contra Faustum Manichaeum, Book XXII, c. 397-398 AD.
2. Augustine of Hippo, Quaestiones in Heptateuchum, Book VI, Q. 10, c. 419 AD.
3. Augustine of Hippo, The City of God, Books XIX and XV, 413-426 AD. Trans. Henry Bettenson (Penguin Classics, 1984).
4. Augustine of Hippo, Epistle 189 (To Boniface) and Epistle 138 (To Marcellinus), in The Letters of St. Augustine, trans. J.G. Cunningham, Nicene and Post-Nicene Fathers, vol. 1 (1886).
5. Thomas Aquinas, Summa Theologiae, II-II, Q. 40, “Of War,” c. 1265-1274.
6. Frederick H. Russell, The Just War in the Middle Ages (Cambridge University Press, 1975).
7. Paul Ramsey, War and the Christian Conscience: How Shall Modern War Be Conducted Justly? (Duke University Press, 1961).
8. Paul Ramsey, The Just War: Force and Political Responsibility (Charles Scribner's Sons, 1968).
9. Jean Bethke Elshtain, Augustine and the Limits of Politics (University of Notre Dame Press, 1995).
10. Jean Bethke Elshtain, Just War Against Terror: The Burden of American Power in a Violent World (Basic Books, 2003).
11. James Turner Johnson, Just War Tradition and the Restraint of War: A Moral and Historical Inquiry (Princeton University Press, 1981).
12. John Howard Yoder, The Politics of Jesus (Eerdmans, 1972), for the pacifist counter-position.