Roland Bainton, the son and husband of Quakers, himself a Congregationalist minister, writes that, originally, “limited war presupposed … conditions which were fulfilled by the Greek city-states;” “independent sovereign states of approximately equal strength” “with forces so well matched that… wisdom pointed to mediation rather than to the arbitration of a long and indecisive conflict” Plato was the forerunner to just war, but never called it that, since conflict amongst the city- states he would not call “war.” Aristotle, in his Politics (I, 1256, B., 23-26), asserted that a just war was one to enslave people to their proper status in the face of resistance. The Roman jurist Cicero adjusted it in his De Officiis (I, 34-40, 83; II, 27; III, 46, 107) for use by states as they existed during his time. He laid the foundation for such tenets as “formal declaration by an authority” based on the Roman practice of Pater Patratus, the ‘father of fathers’ of the Fetiales in the Fecial College (not unlike the bishop of bishops in contemporary Roman Catholic tradition). Bainton leaves unclear whether and to what extent this practice of the Fetiales derived from Deuteronomy, in which Israel appeals for peace and provides a time for response before waging war. However, given the sacred nature of both war and peace in ancient era, it may simply be that it was common practice to avoid conflict at all costs, even up to the last. Cicero also insisted upon an “adherence to oaths” between enemies and friendlies. He maintained no protection of noncombatants, but the vanquished were spared humiliation and guaranteed full citizenship. Bainton recalls concrete examples of this occurring.
Many centuries after Cicero, Bainton recounts the first Christian account of justified war to be by Ambrose. The bishop of Milan’s position as a praetorian prefect would have inclined him against the instinct to exclude soldiers in the same vein as Tertullian or Origen. He revived what Cicero advocated for and added that the “conduct of war should be just and that monks and priests should abstain.” Mentored by Ambrose, Augustine watched as the Roman Empire began to collapse. His view of human nature allowed him to make a distinction between act and attitude, giving space for an ethic that “served to justify outward violence.” In writing to Boniface, he pleaded with the Roman general to put off interest in monasticism in order to help in protecting the empire, which Augustine all too quickly equated with the faith. [Here one could draw direct parallels with Niebuhr, who too appealed to the state for preservation of culture, including religion] Bainton cites that for Augustine, war’s intent was to be just, its disposition love, and its auspices just. With Cicero, Augustine insisted, “Faith must be kept with the enemy.” The authority bestowed upon soldiers under oath ensured moral sterility; meaning private citizens could not take life, for to do so would be a product of the passions and self-assertion. Finally, and this final point is taken up in the modern era quite robustly, justice rested upon one side of the conflict only. Bainton reflects that with the modern world’s attention to the margins and its inherent liberative instincts, the suggestion that justice can be on both sides of the war is valid (however much that throws off our moral considerations).
At the outset of the second millennia, Bainton describes just war as having faded while a kind of anarchy prevailed in the church, which gave way eventually to the phenomenon of the crusade. Bainton recounts numerous episodes in which clergy took up arms even while the just war shifted focus from protection of life and honor to the protection of property. Rebellions were forbidden in the increasingly feudal society by the determination that “an inferior ruler could not make war upon a superior ruler,” though such a leveling would be hard to determine without question given the agrarian nature of society compared to the relatively unified pluralism of Rome. Aquinas, therefore, was a product of his time in focusing on the issue of property in his deliberations on war, based upon natural law and the relationship between land, harvest, and feudal survival. He introduced the tenet of proportionality; that a just war may not “destroy more property than it recovered.” Abelard was the first to confront the issue of conscience, finding that the “conscience is obligatory though not exempt from the consequences.”