Charles J. Reid, Jr.
James Brundage and I first became acquainted in the spring of 1978, when I enrolled as an undergraduate in his class on the history of medieval law at the University of Wisconsin-Milwaukee. I enjoyed the class so much I did directed research with Jim the following year, exploring the treatment of soldiers’ wills in medieval Roman and canon law. Jim had by this time given me as well an abiding interest in the history of warfare and that most paradoxical of medieval enterprises—the effort to place legal restraints on a process that might otherwise know no boundary. And when, in the 1980s, I organized a series of symposia that concluded in my editing a book on the bishops’ pastoral letter on nuclear arms, I knew to ask Jim to contribute a chapter on the earlier canonistic effort to supply moral guidance to military conduct.1 Modern bishops and medieval canonists, it seemed, had much in common.
This chapter draws on some of my work on the origin of individual rights in medieval law to examine the operation of the related, but distinct, rights of self-defense and justified warfare. To speak of rights in the context of medieval law challenges some old and cherished suppositions. An earlier school of thought had maintained that if rights existed at all in medieval jurisprudence, they were a vague and subordinate concept. Thomas Aquinas, on this account, had created a system of thought based on an objectively just apportionment of goods which was shattered by the invention of subjective rights in the work of William of Ockham or Thomas Hobbes, depending on whom one reads.2
We know now, of course, that the medieval canonists had a full and robust understanding of individual rights. Rights (iura) were seen variously as faculties, powers, liberties, or interests of the individual, and might function as trumps that restrained arbitrary action on the part of those with power.3 Many of these rights, including the rights of self-defense and justified war, were considered natural rights, that is, rights derivable from nature and accessible to all those with reason and good will.4 In this respect, the rights of self-defense and justified war belonged in the same category as the right of the poor to sustenance, the right of married couples to conjugal relations, the right of offspring to claim a portion of parental inheritances, and other claims the justness of which seemed self-evident to the medieval legal mind.
Medieval jurists confronting the idea of a right of self-defense had to contend with a tradition that had at least in part questioned this proposition’s legitimacy. It seems self-evident that any theory of just war should begin with the right of self-defense, but this was not self-evident to St. Augustine, the source of so much of the medieval just war tradition, who argued that fundamentally there was no right of personal self-defense.
To St. Augustine, one must always prefer the eternal and the spiritual over the transitory and the temporal. Thus one who defended oneself by taking the life of another sinned, since he preferred the preservation of his own transitory, mortal existence over greater spiritual goods, and so almost certainly acted with libido, best translated as excessive desire or passion.5
At the same time, however, St. Augustine was willing to justify the public taking of life by reference to the principles of Christian charity: public officials, properly motivated by Christian love and keeping foremost in their minds the need to maintain public order, might kill in warfare so as to preserve the peace and restrain sinfulness.6
Classical Roman law, on the other hand, began its analysis from the intuitively obvious starting point of self-defense. An excerpt of Florentinus taught that one might properly resist force with force so as to prevent injury and to protect one’s physical well-being.7 Ulpian added that such resistance was licit only if it was done ex incontinenti—“at the time of the attack”— rather than ex intervallo, “after a delay.”8 An excerpt from Paulus pronounced that “all statutes and all iura permit the use of force to defend against force.”9 Iura here might mean either “laws” or “rights.”
A decree of Diocletian permitted the use of “moderate” force in the protection of one’s property.10 A colorfully-worded statement by the Emperors Valentinian, Theodosius, and Arcadius added that all persons had a “free faculty of resisting” intruders with deadly force, since, they reasoned, it was better to resist in this world than to litigate in the next.11 A worldly, earthly pragmatism here trumped the theological. This appreciation for the practical was in keeping, however, with long Roman tradition. As early as the Roman Republican period, Cicero grouped self-defense as among the actions authorized by the ius naturae.12 Resistance, however, had to be proportionate to the threat. As the Roman jurists put it, a moderate self-defense was blameless (moderamen inculpatae tutelae), but an excessive defense counted as murder.13
War, at Roman law, was conceptually distinct from personal self-defense. It required a just cause, a public declaration of hostilities, and carried with it a set of rights and duties incumbent upon the participants.14 War, in the Roman world, was an accepted, even routine part of statecraft, provided the proper forms were followed.15 Indeed, it was even taught by Justinian that war itself was a part of the ius gentium, the law of nations found among all civilized peoples.16
War, according to at least one classical Roman source, was about the restoration of one’s ius. Livy, in describing how war was commenced in the early days of the Republic, stated that one of the fetiales, priests who had among their duties the declaration of war, would announce to the enemy that he had come as a public representative of the Roman people. His task was to call down judgment on the enemy because they had not made proper amends (neque ius persolvere), and so the elders of Rome would now take counsel how their right (ius nostrum) might be restored.17
In this passage one sees Livy moving fluidly between objective and subjective understandings of ius, as war was conceived even in Livy’s day as both a restoration of just order and a restoration of certain public rights. This understanding of war as restorative of just order and injured rights would come to be systematized by the medieval canonists of the twelfth and thirteenth centuries.
The Decretum’s treatment of self-defense and war incorporated elements from both Augustinian theology and Roman law.19 Its analysis of personal self-defense contained some potentially contradictory elements. On the one hand, the Decretum includes a decree of the fourth council of Carthage, representing the old suspicion against self-defense, which denied clerical promotion to those who avenged their own injuries.20 This choice of texts, however, was countered with an excerpt from Isidore of Seville who had borrowed from Roman sources to reiterate the point, going back to Cicero, that the repulsion of force by force was a part of the natural law.21 No effort was made to reconcile these passages, which were placed in different parts of the Decretum.
The Decretum’s analysis of justified warfare, however, was more coherently arranged, grouped as it was under the heading of a single causa—Causa 23. This section of the Decretum, which amounts to a small treatise on war, commences with some dialectically arranged biblical propositions. Warfare, it is maintained, is alien to the Gospel.22 The standard texts were mustered to support this conclusion. We must turn the other cheek when struck; we should walk two miles with another when forced to walk one; we should not judge, lest we be judged; and other like texts were deployed to support what seemed like a self-evident proposition: Christians were forbidden to wage war.23
The Decretum, however, follows these passages with some generous samplings of St. Augustine’s argument that the Gospel teachings were merely intended to guide the inward disposition of the heart.24 They did not dictate a policy of pacifism, but only provided a guide to individual conscience. One should be patient and loving even when waging war, but in an imperfect and fallen world, where sinners must still be restrained and the innocent and the vulnerable protected, war cannot be said to be excluded by the Gospel.25
The Decretum went on, in Causa 23, quaestio 2, to consider how a particular war might be said to be just. This quaestio opens with an excerpt from Isidore of Seville which declared war to be just when fought in accord with an edict for the recovery of goods or the repulsion of attack.26 In a seeming aside, the text, as excerpted, added that it was a just judge who spoke ius and decided cases in accord with ius who presumably was qualified to declare war.27 The Decretum subsequently endorsed this encapsulation of the just war in a dictum.28 In this way, one sees the conferral on rightful authority of the responsibility for declaring war and the premising of such a determination on a finding that the order of justice has been violated and must be restored.
The Decretum also contains texts relevant to just war in its first distinctio, part of the “Treatise on Laws.”29 Mention has already been made of the Isidorian text, known as Ius naturale, which grounded self-defense on the natural law.30 A second text of Isidore’s, again epitomizing Roman law, declared war to be a part of the ius gentium.31 In yet another excerpt, Isidore identified the subject-matter of the ius militare, “military law,” as including the solemnities of declaring war, the forging of alliances, the maintenance of martial discipline, and other such matters.32 The Decretum did not comment on either of these latter two excerpts, taking for granted the picture presented of the right to wage war.
A careful reading of the Decretum’s sources, and the manner in which they were edited and deployed, would thus lead a reader to conclude that the right of self-defense was grounded on natural law while the right to wage war was grounded on the law of nations. The decretists who followed Gratian were forced to come to terms with these seemingly contradictory foundations. Over time, in the course of reconciling these varying sources, the decretists tended to collapse the distinction between personal self-defense and the waging of war, while moving away from the Augustinian aversion to self-defense. Indeed, it is clear that the decretists sought to carve out a unified theory of a basic right of self-defense that encompassed both personal acts of self-preservation and justified warfare within the terms of its analysis.
Rufinus, who wrote his Summa on the Decretum around 1160, sought to retain the Isidorian distinction between a natural right of self-defense and a right of war grounded on the ius gentium. Rufinus asserted that the simple repulsion of force by force belonged to the ius naturae because it seemed that nature had taught this much to all animals.33 The vindication of legally cognizable injuries, however, which was the peculiar subject-matter of warfare, belonged to the ius gentium, since only men, not animals, can be said to do or permit injuries.34
By the time one arrives in the 1190s, however, one finds a different picture. The Summa, “Induent Sancti” considered directly whether warfare was in accord with the natural law. It seemed, the anonymous author began, that it is not. Peace is the first teaching of the natural law, as embodied in the Golden Rule.35 The introduction of “dominion” (property, lordship), however, which came into being because of human sinfulness, led to wars, captivity, and slavery. Since man cannot himself dispense from the natural law and thus remained obliged to obey its first precepts, it is clear that God must have dispensed from these first terms, although the Summa’s author is at a loss to know when this dispensation occurred.36 In any event, God did dispense from the natural law’s primitive requirements, and so warfare became a licit activity, in conformity with natural law, provided it is waged justly.37 On this analysis, the author noted, military service is an affirmative good, provided that one acts in self-defense and to keep the peace.38 Indeed, an armed self-defense is a right conceded in our fallen present state to all men by the natural law.39
Johannes Teutonicus made the same point more tersely but equally effectively. He freely allowed that it was possible to repel injuries with force and supported this conclusion with a reference to Isidore’s reliance on the natural law to justify self-defense.40 Johannes proposed that this principle might be so all-embracing as to allow even direct clerical participation in war, although he subsequently qualified this view severely.41 Throughout his analysis, Johannes simply took for granted that he was addressing organized combat, not personal self-defense. Unlike Rufinus, Johannes attached his commentary to Causa 23, not distinctio one.
The right to wage war in some decretist analysis was thought to include self-help. This is illustrated by a gloss of Rolandus’s on the waging of war in order to gain safe passage through third countries. War, Rolandus asserted, is sometimes permitted, even in the absence of jurisdiction and competent authority, where the natural law has been violated.42 The example Rolandus gave was the war waged by the Israelites against the Amorites when the latter group refused to grant the Jewish nation safe passage through their territory.43 In ordinary circumstances, however, Rolandus conceded that those waging war required the potestas inferendi belli, the power to make war, which he associated with jurisdiction.44
In fact, for most of the decretists the authority to wage war was a fundamental part of their analysis of a given war’s justice. Rufinus argued that war should not be counted as a sin where it was just and waged at the direction of “public powers.”45 The Summa parisiensis pronounced as just those wars waged by princely edict against publicly determined enemies for the recovery of goods or the vindication of injuries.46 A war waged without princely authority is “without doubt unjust.”47 The Summa “Elegantius in iure divino” forbade the taking up of arms on private authority (sua auctoritate), admonishing that this could be done only by the “public power” (publica potestate) of the ruler.48 St. Augustine, the Summa’s author reasoned, required as much when he recognized the “authority to wage war” (“suspiciendi belli auctoritate … penes principles”) was given princes in order to preserve the peace.49
This authority came to be denominated the right to wage war. Thus Alanus Anglicus spoke of the “right of waging war” (ius indicendi belli) that belonged to princes. Alanus included among the princes who had this power even some who had nominal superiors, such as the rulers of northern Italian communes.50 Other texts, such as the Summa “Induent Sancti”51 and the Glossa ordinaria to the Decretum52 spoke of the “right of the sword” (ius gladii) which belonged to princes.
The decretalists who commented on the steady stream of papal decretal letters which issued forth from the papal chancery in the late twelfth and thirteenth centuries adopted as their own the decretists’ battery of ideas and vocabulary when analyzing the question of the licitness of war. Raymond of Peñafort, synthesizing the preceding debate, proposed that a war might be just provided five criteria were satisfied: war must be directly waged by secular rulers, not ecclesiastical ones; it must have as its object the recovery of goods or the defense of the homeland (patria); its end must be peace; it must be fought not from a spirit of domination, hatred, or vengeance, but out of a spirit of love, justice, and obedience; and its authorization must come either from the prince, or from the Church, when it acts to defend the faith.53
Raymond also asked whether in the absence of princely or ecclesiastical authority the natural law might serve as grounds for waging war.54 He answered by distinguishing between an attack on persons and an attack on property. A defense of one’s person is allowed, provided one is genuinely threatened with lethal force and the resistance is proportional.55 Raymond was also willing to tolerate a forceful defense of property, provided the defense was “immediate” (in continenti).56 “Vengeance,” however, was not tolerated either in the defense of one’s person or property, and was to result in excommunication.57
The decretalists, like the decretists, also employed rights language to analyze the authority by which rulers waged war. Innocent IV’s analysis of this question makes clear the role played by rights in the decretalist treatment of war.58 Innocent identified three levels of violence, each of which demanded separate analysis.59 It is permitted to all persons, Innocent observed, to wage war (movere bellum) in defense of one’s persons and things, although such action is not properly called war but “defense” (defensio).60 One does not require princely authority to act in self-defense, provided one acts at once; rather, one acts on the authority of ius itself.61 (Ius in this context clearly meant the power to act in conformity with the requirements of a transcendent natural law—a neat combining of subjective and objective elements of “right” that is impossible in English but that regularly occurs in the Latin of ecclesiastical jurists).
But what of the person whose property has been taken and is unable to prosecute his claim (ius)? It is everywhere permitted in these circumstances to rely upon the authority of a superior who will take up arms on one’s behalf and wage war so as to recover what has been taken.62 But where the authority to whom one has had recourse himself has a superior—as Innocent puts it, where he has a prince over him—then action may only be taken where the ultimate superior has consented. Innocent resorted to rights language to explain this layered relationship: such an arrangement seemed just, Innocent reasoned, since it is permitted to no one to tamper with rights without the permission of the source of those rights.63 The prince’s rights must not be put in doubt by the unauthorized actions of a subordinate.
Innocent then turned to the third type of conflict—war waged by a lord with the right to wage war (ius indicendi bellum). A prince who has no superior is always able to wage war against the subjects of another prince who have provoked the attack.64 This right, Innocent noted, even belonged to prelates who held temporal jurisdiction, who, although forbidden to engage directly in hostilities, might prosecute war and exhort their troops to fight the enemy and capture them, but not command their deaths.65 This last distinction was no doubt lost on many of the bishops who exercised temporal jurisdiction.66
Innocent’s proposal had the advantage of responding to the reality of warfare in medieval Europe and of seeking realistic ways to curb its effects. War, after all, throughout this period, was typically “proprietorial,” involving feudal lords who exercised power that combined elements of landownership and sovereignty, and who had constant recourse to arms to settle local squabbles.67 By limiting the scope of the war-making authority of feudal lords with superiors, Innocent IV had a real chance, or so he must have hoped, of restricting the constant petty struggles that continued to plague Western Europe in the thirteenth century.68
Hostiensis, on the other hand, made use of rights language in order to support far more drastic restrictions on the right to wage war. In his Summa, Hostiensis commenced his analysis of the just war conventionally enough by summarizing Gratian’s teaching that war was not sinful provided it was waged by a prince, acting in self-defense, or in defense of his patria or ancestral laws.69 There were, he continued, five ways in which a war might be unjust—by reason of its subject-matter (res), that is, where the war was not fought for the recovery of lost property or in defense of the homeland; or by reason of cause, where the war was “voluntary” and not necessary (we might today call this a “war of choice”); or by reason of intention, where it was undertaken in the spirit of vengeance; or by reason of absence of authority, where the prince lacked the power to prosecute the war; or by reason of person, such as where clerics participated directly in the fighting.70
Hostiensis focused much of his analysis on the question of proper authority. The princes of the Christian West, he asserted, constituted a single “Roman people” and were bound together by a certain right/law of familial relations (ius cognationis).71 This right, Hostiensis asserted, expanding on his Roman-law sources, arose from nature and was a public ius that could not be renounced by contract or other agreement of the parties. Those who were bound to one another by right of cognation, Hostiensis continued, could not wage war against each other without committing diffidatio, the feudal crime of disloyalty which placed one outside the pale of civilized society.72 Hostiensis proposed that such outlaws were themselves to be punished militarily because it was generally prohibited to speak right (ius) for oneself and because they were transporting arms without the knowledge of their superiors.73
The ius cognationis, which English speakers are forced to translate either as law or as right, here clearly carried both objective and subjective meanings at once, characterizing both the objective relationship of cognatio and the rights that arose as a result of this relationship. It was both the bond that obligated Christians to deal with one another peaceably and the right and expectation of peaceful intercourse.
But the relationship which bound Christian princes into a single extended family did not thereby mean that Christians should embrace pacifism. Hostiensis still allowed for some types of war, which he explored in his Summa and in greater detail in his commentary on the letters of Innocent IV. In the latter work, which incorporated and expanded upon many of the arguments found in the Summa, Hostiensis chose the conciliar decree Pro humani redemptione, issued by the First Council of Lyon for the purpose of deposing Frederick II as German Emperor, as the subject of his analysis.74 Hostiensis reiterated that ordinarily a Christian might not make war against another Christian since all Christians shared the bond of the ius cognationis which was introduced by nature and made firmer by the divine command to love one another.75
In spite of this limitation, Hostiensis was nevertheless prepared to sanction several types of warfare. The first was “Roman War,” by which Hostiensis meant the crusades, led by Rome, the seat of faith (caput fidei) against the faithless (infideles).76 A second type of licit war was that authorized by a judge holding the merum imperium who did not pronounce ius for himself but who preserved the legal order and sought by his sentence to punish contumacy.77 The other two licit forms of war, Hostiensis added, were those launched by one so authorized for the protection of his “neighbors” and the repulsion of injuries;78 and those resulting from immediate self-defense.79 All other forms of warfare were condemned as illicit and unjust.80
In speaking of “Roman War” and in establishing a sharp juxtaposition between Christians and those outside the fold, Hostiensis was hearkening to the idea of a unified Christianitas that contained within itself both temporal and spiritual spheres but that also stood in opposition to the outside world.81 These temporal and spiritual spheres were never entirely collapsed into one another—canonists and theologians always sought to acknowledge that each sphere had a core competence that the other could not intrude upon. Indeed, even so powerful a spokesman for the “hierocratic” view of the relation of the two powers as Hugh of St. Victor wrote of the requirement that the right of the temporal realm be kept secure from undue invasion by the spiritual.82
But the basic problem that remained was to define what belonged by right to the temporal sphere and what belonged to the spiritual and, since the spiritual realm was more exalted than the temporal, what was the nature of the governance to be exercised by the spiritual over the temporal. To answer this question, popes, theologians, and canonists began to speak of a coercive power that the Church might exercise over the temporal realm where secular rulers had gone badly astray.83 This power was also conceptualized as a ius.84 Bernard of Clairvaux, for instance, writing to Pope Eugenius III, spoke of Christ’s right of creation (ius creationis), which gave Him possession and dominion over the world.85 The pope, as caretaker of this right, was given broad responsibilities over the temporal sphere.86 Thus Bernard admonished the pope to put on the sword of the spirit, which was the Word of God, and to “glory in His hand and right arm in striking vengeance upon the nations, rebuking people and binding their kings in chains and their lords in iron manacles.”87
Legal texts reflected a similar attitude. Indeed, as James Brundage has well documented, a whole ideology of holy war, which viewed warfare not only as necessary but as salvific, emerged from this sort of exalted sense of ecclesiastical power.88 Quaestio eight of Causa 23 represents both the culmination of theorizing that had been going on since the heady days of the Gregorian Reform and the starting point of subsequent analysis. The Decretum commenced its arrangement of texts by declaring, for dialectical purposes, that clerics lacked all authority to wage war. After all, Jesus had instructed Peter in the Garden to sheath his sword, admonishing him that all who take up the sword will perish by it.89 The Decretum followed this assertion with a series of texts establishing that while clerics were not to participate directly in combat,90 historically they did take a leading role in directing how and when force might be used. Especially important were three texts of Pope Leo IV, written in connection with his defense of the City of Rome from Saracen attack,91 a text of Alcuin recounting Pope Adrian’s leading role in urging Charlemagne to campaign against the Lombards,92 and an excerpt from a letter of Gregory the Great on his organization of the City’s defenses in 591.93
Hostiensis drew deeply on this tradition when he wrote of the responsibility of clerics to exercise the rights entrusted to the Church (ecclesiae sibi commissae iuribus exercere) and to encourage the laity to fight in just wars, which included especially Roman War.94 His authorities for this assertion were the Leonine and Gregorian texts cited above.95 Clerics, Hostiensis asserted, might prosecute a war and exhort the combatants, provided the war was in self-defense or for the recovery of the rights of the Church (pro defensione vel recuperatione iurium ecclesiae).96 On the other hand, the instigators of an unjust war, of the sort prohibited to all Christians, have thereby sinned and ought to be deposed and be subjected to the full rigor of the law.97
In his Summa, Hostiensis considered whether this right of the Church to prosecute crusades ought to be extended against the heretics of Western Europe.98 Hostiensis noted that some lawyers disagreed with the proposition that the crusading power might lawfully be extended to include wars against schismatics and other “disobedient rebels” but, he went on, not every action required an express ius for its undertaking.99 If taking the Cross to fight the Saracens in the Holy Land was meritorious, how much more meritorious might it be to fight on behalf of the unity of the Church at home?100 Citing the Decretum’s Causa 23, quaestio one, Hostiensis asserted that this power should be limited to the pope alone since it was his responsibility to see to the defense of the faith.101 Citing the passages from the Decretum that connected self-defense and natural ius, Hostiensis found further support for ecclesiastically-backed military campaigns against heretics in the natural right of self-defense.102 Innocent IV and Bernard of Parma reached conclusions similar to Hostiensis’s about the Church’s power over heretics and schismatics, but by means of far briefer analysis.103
Thus it was that thirteenth-century canonists came to deploy rights language to analyze the war-making power. Princes without superiors, at least on Innocent IV’s account, were held to enjoy the right to wage war. On Hostiensis’s account, the Church itself, through its representative the pope, came to claim an ultimate right to direct the warfare of Christian subjects, against Saracens in the Holy Land and against heretics and schismatics and disturbers-of-the-peace within the boundaries of Christendom. This analysis was accomplished by use of a sophisticated rights vocabulary. Basic principles, such as the natural right of self-defense, and various rights-based concepts, such as the ius indicendi belli, the ius gladii, and the ius cognationis helped to build the edifice of medieval just-war theory.
This rights-based analysis of war would come to shape legal and political thinking for generations to come. Johannes de Legnano (c. 1320–1383), a doctor of civil and canon law, a Bolognese diplomat as well as a law professor,104 and “the author of the first full-fledged treatise on the law of war,”105 commented extensively on the rights of war.106 Legnano distinguished among various types of warfare—spiritual warfare, both celestial and earthly,107 and corporeal warfare, either universal, that is waged by publicly-constituted authorities, or particular, that is waged by an individual or community resisting attack in the absence of superior authorization.108
The right or faculty of waging just war—the facultas belli indicendi iusti in Legnano’s language—was introduced by God as a matter of divine law to serve affirmative goods, such as the restoration of peace and the punishment of the wicked.109 Indeed, God Himself, in the Old Testament, provided the paradigm of good and just wars that both punished wrong-doers and sought more generally to exterminate evil.110 Just war, Legnano continued, was also in conformity with the natural law. Just as a physical body is sometimes afflicted with an “excess of humors” that requires purging, so the political community is sometimes afflicted with an excess of rebellion which tends to the destruction of good governance and can be remedied by the “medicine of an eradicative and exterminative war against evil-doers.”111
Legnano understood the right to wage earthly war to belong, first of all, to the Church, which might declare war against infidels and authorize the invasion of their lands.112 Although recognizing that infidels retained some rights of self-government,113 Legnano also stressed that the pope enjoyed de iure jurisdiction over non-Christians and could hold them to the observance of the natural law.114 Where required, the pope may also wage war against any heretic, schismatic or usurper of ecclesiastical rights (iura et libertates ecclesiarum), including even the emperor.115 Furthermore, Legnano went on, this war-making power belonged not to the pope alone, but also to bishops, provided that they are defending their own rights (sua iura).116
Tacitly repudiating Hostiensis’s effort to limit war among Christian princes, Legnano acknowledged that all secular princes without superiors, especially the emperor, also enjoyed the right to wage just war.117 Echoing Innocent IV, Legnano explicitly denied to those with superiors the right to wage war, since this would be to violate “the rights of princes” (iura principum).118
A quarter of a millennium after Legnano wrote, one finds Hugo Grotius still analyzing warfare in terms of rights. Gone from Grotius is any acceptance of a right of the Church to wage war. But in other respects, his analysis is one the canonists would appreciate. Grotius wrote variously of the “right of conducting war” (jus habere belli gerendi) and the “right of moving arms” against a foe (jus armorum movendorum).119 Citing Dionysius of Halicarnassus as support, Grotius found the “moral faculty” of governing a state to consist in three rights: the right to name subordinate office-holders; the right to make and abrogate laws; and the right to make decisions of war and peace.120 He noted that because the waging of war endangers the entire state, it is the law nearly universally that only the supreme power in the state (summa potestas) has the right to wage war.121 There have certainly been debates regarding the extent to which Grotius should be considered representative of a new way of viewing international law, debates which we have no intention of resolving here.122 But it can fairly be stated that Grotius’s rights-based reasoning on the power to declare and wage war was by the time he wrote at least 400 years old.
In the aftermath of the attacks of September 11, 2001, the vocabulary of a right of justified self-defense has gained renewed currency. A joint resolution of the United States Senate and House of Representatives enacted following the attacks endorsed the proposition that it is “both necessary and appropriate that the United States exercise its rights to self-defense and to protect United States citizens both at home and abroad ….”123 Official American spokespersons have reiterated the national right of self-defense,124 as have prominent private citizens.125 Pope John Paul II similarly endorsed a right of self-defense,126 although he admonished that the prevention of conflict requires that a different set of rights also be respected.127
The idea of a basic, even natural right of self-defense has a long pedigree and is very appealing, especially in the light of surprising and deadly attack. A word of caution, however, is also appropriate. The right of self-defense can, altogether too quickly, transform itself from tragic necessity into affirmative good, as in the work of a writer like Johannes de Legnano. An abstract right such as self-defense can also serve to mask the human suffering that is inevitably inflicted in its name. Human passion, “war-lust,” or libido, to use St. Augustine’s language, remains a constant danger to the morality of a conflict. There is the further danger of warfare as ideological conquest. The line between self-defense and crusade was one the canonists themselves often blurred. In this way, war becomes domination by another name. When taking up arms, one must be wary about crossing these thresholds.
1 See James A. Brundage, “The Limits of the War-Making Power: The Contribution of the Medieval Canonists,” in Charles J. Reid, Jr. (ed.), Peace in a Nuclear Age: The Bishops’ Pastoral Letter in Perspective (Washington, DC, 1986), pp. 69–85.
2 On Ockham, see Michel Villey, “Les origines de la notion de droit subjectif,” in Leçons d’histoire de la philosophie du droit (new edn, Paris, 1957), pp. 221–250; and Michel Villey “La genèse du droit subjectif chez Guillaume d’Occam,” Archives de philosophie du droit, 9 (1964): pp. 97–127. On Hobbes and an early modern origin for subjective rights, see Leo Strauss, Natural Right and History (Chicago, IL, 1950), pp. 120–164. These views remain persistently held by some. See G.R. Evans, Law and Theology in the Middle Ages (London, 2002), p. 32.
3 See Charles J. Reid, Jr., “Thirteenth-Century Canon Law and Rights: The Word ius and Its Range of Subjective Meanings,” Studia canonica, 30 (1996): pp. 295–342; and Charles J. Reid, Jr., “The Canonistic Contribution to the Western Rights Tradition: An Historical Inquiry,” Boston College Law Review, 33 (1991): pp. 72–91 especially.
4 On medieval natural rights, see Brian Tierney, The Idea of Natural Rights: Studies on Natural Rights, Natural Law, and Church Law, 1150–1625 (Atlanta, GA, 1997), pp. 43–235 especially.
5 See St. Augustine, De libero arbitrio, I. 5. Cf. David A. Lenihan, “The Just War in the Work of Saint Augustine,” Augustinian Studies, 19 (1988), pp. 37, 42–44, and 60–62.
6 See Louis J. Swift, The Early Fathers on War and Military Service (Wilmington, DE, 1983), pp. 110–160; and Louis J. Swift, “Search the Scriptures: Patristic Exegesis and the Jus Belli,” in Reid (ed.), Peace in a Nuclear Age, pp. 48, 58–68.
7 Digest 1.1.3.
8 Digest 43.16.3.9.
9 Digest 9.2.45.4: “vim enim vi defendere omnes leges omniaque iura permittunt.”
10 Codex 8.4.1.
11 Codex 3.27.1: “liberam resistendi cunctis tribuimus facultatem … Melius est occurrere in tempore, quam post exitum vindicare.”
12 See Cicero, De inventione, bk II, 53.161.
13 See Frederick H. Russell, The Just War in the Middle Ages (Cambridge, 1975), p. 42.
14 See Alan Watson, International Law in Antiquity: War and Religion (Baltimore, MD, 1993), pp. 20–30 and David J. Bederman, International Law in Antiquity (Cambridge, 2001), pp. 222–227, 231–241.
15 See Bederman, International Law in Antiquity, pp. 222–227.
16 See Institutes 1.2.2 and Digest 1.1.5.
17 See Titus Livius, Ab urbe condita, 1.32.9. Cf. Watson, International Law, pp. 10, 24, and 77.
18 I am using the word Decretum here and elsewhere in this chapter as a way of recognizing that we can no longer speak of this work as the product of a single individual who published this work at a given point in time. Rather, we must acknowledge, following Anders Winroth, that this foundational work of canon law came into being in stages, and was the work-product of at least two, and perhaps more, legal minds working over a span of some two decades. See generally, Anders Winroth, The Making of Gratian’s Decretum (New York, 2000).
19 On Gratian’s analysis of war, see Russell, Just War in the Middle Ages, pp. 55–85; Alfred Vanderpol, Le Doctrine scolastique due droit de guerre (Paris, 1919), pp. 287–299; and Robert Regout, Le doctrine de la guerre juste de Saint Augustin à nos jours (Paris, 1935), pp. 61–66.
20 D. 46 c. 8.
21 D. 1 c. 7.
22 C. 23 q. 1 pr.
23 Ibid.
24 See C. 23 q. 1 cc. 2–7.
25 C. 23 q. 1 d.p.c. 7.
26 C. 23 q. 2 c. 1.
27 Ibid.
28 C. 23 q. 2, d.p.c. 2.
29 See Gratian, Treatise on Laws (Dist. 1–20), trans Augustine Thompson and James R. Gordley (Washington, DC, 1993).
30 D. 1 c. 7.
31 D. 1 c. 9.
32 D. 1 c. 10.
33 See Rufinus of Bologna, Summa Decretorum, ed. Heinrich Singer (Aalen, 1963), D. 1 c. 7 (v. terra marique capiuntur).
34 Ibid.
35 See Summa, “Induent Sancti,” ed. Richard M. Fraher (PhD dissertation, Cornell University, 1978), p. 566, C. 23 q. 2.
36 Ibid.
37 Ibid., pp. 566–567.
38 Ibid., p. 565, C. 23 q. 1.
39 Ibid.: “Ex causa autem defensionis militare regulare bonum est omni homini, quia iure naturali est concessa defensio ….”
40 See Johannes Teutonicus, Glossa ordinaria, C. 23 q. 1 d.a.c. 1 (v. propulsandam). Cf. D. 1 c. 7.
41 Ibid.
42 See Summa Magistri Rolandi, ed. Friedrich Thaner (Aalen, 1962), p. 88, C. 23 q. 2.
43 Ibid. Cf. Numbers 21:21–25.
44 Ibid., p. 89, C. 23 q. 3.
45 See Rufinus, C. 23 q. 1 pr.: “militare non est peccatum, dummodo publice potestates bello gerendo presideant.”
46 See The Summa Parisiensis on the Decretum of Gratian, ed. Terence P. McLaughlin (Toronto, 1952), p. 211.
47 Ibid.: “Si igitur bellum fiat quod ex edicto geratur … injustum prcul dubio est.”
48 See Summa “Elegantius in Iure Divino,” eds Gerard Fransen and Stephan Kuttner (4 vols, Vatican City, 1986), vol. 3, p. 216.
49 Ibid., pp. 216–217.
50 See Alanus Anglicus, C. 23 q. 2 c. 1 (v. ex edicto). Also quoted in Russell, Just War in the Middle Ages, pp. 139–140, n. 40 and n. 41).
51 See Summa “Induent Sancti,” p. 574, C. 23 q. 8.
52 See Glossa ordinaria, C. 23 q. 4 c. 16 (v. casus).
53 See Raymond de Peñafort, Summa de Paenitentia, eds Xavier Ochoa and Aloisio Diez (Rome, 1976), bk. II, title 5, cols 485–486.
54 Ibid., col. 486.
55 Ibid., cols 486–487. Raymond gives as an example of proportionality: one may resist an armed attacker with arms, but not an unarmed attacker. Ibid., col. 487.
56 Ibid., col. 488.
57 Ibid., col. 487.
58 See generally Frederick H. Russell, “Innocent IV’s Proposal to Limit Warfare,” in Stephan Kuttner (ed.), Proceedings of the Fourth International Congress of Medieval Canon Law, Toronto, 21–25 August 1972 (Città del Vaticano, 1976), pp. 382, 386–388.
59 See Innocent IV, Apparatus (Frankfurt, 1570), X. 2.13.12 (v. respondemus).
60 Ibid.
61 Ibid.: ‘[E]t cum hoc a iure sit concessum, nec est authoritas principis necessaria ….” Innocent here seems to assume that the ius to which he is referring is natural law/right.
62 Ibid.: “Item ubicunque per alium rem suam, et ius suum prosequi non potest, licitum est authoritate superioris arma movere, et bellum indicere ad recuperandum sua ….”
63 Ibid.: ‘Et hoc videtur iustum, quia nulli licet iura temperare sine authoritate conditoris iurium.” Thomas Aquinas also used rights language to explain this relationship: “For it does not belong to a private person to wage war: Because one prosecutes one’s right in a superior’s court.” (“Non enim pertinet ad personam privatam bellum movere: quia ius suum in iudicio superioris prosequi.”) See Summa Theologiae, 2a 2ae, q.40, art.1, resp.
64 Ibid.
65 Ibid.
66 Such as the bishops described by Timothy Reuter in “Episcopi cum sua militia: The Prelate as Warrior in the Early Stauffer Era,” in Warriors and Churchmen in the High Middle Ages: Essays Presented to Karl Leyser (London, 1992), pp. 79–80.
67 See John France, Western Warfare in the Age of the Crusades, 1000–1300 (London, 1999), pp. 1–15 and 39–52 especially.
68 See Russell, “Innocent IV’s Proposal,” p. 390 especially.
69 See Hostiensis, Summa (Lyon, 1537), bk I, De treuga et pace, sec. 3.
70 Ibid., at sec. 4.
71 “Cognation,” Buckland asserted, “was broadly any blood relationship.” See W.W. Buckland, A Text-Book of Roman Law from Augustus to Justinian, revised by Peter Stein (3rd edn, Cambridge, 1963), pp. 370–371. See also Adolf Berger, Encyclopedic Dictionary of Roman Law (Philadelphia, PA, 1953), p. 393.
72 Hostiensis, Summa, bk I, De treuga et pace, sec 4: “It seems that war which every day the princes of our time wage is unjust. For they are not able to set aside their breach of faith. And since nature has established among us a certain right of cognation it is wrong for man to set snares for man. And this right cannot be renounced by agreement … even if the parties consent in turn.” (… videtur quod bellum tota die exercent principes nostri temporis est iniustum. Et quod etiam per diffidantiam fidem sibi remittere non possunt, cum enim natura inter nos quoddam ius cognationis constituerit hominem homini insidiari nephas est … Hoc ius per pactum renunciari non potest … si ad invicem consentient ….) On diffidatio, see Russell, Just War, p. 142.
73 Ibid.
74 For the text of the decree, see Norman P. Tanner, Decrees of the Ecumenical Councils (2 vols, Washington, DC, 1990), vol. 1, pp. 290–291.
75 See Hostiensis, Super Sexto Decretalibus (Venice, 1581), De homicidio voluntario, c. 1 (v. diffidatus): “Christianus Christianum non debet offendere nisi diffidaverit … [I]deo dicit lex quod cum natura inter nos ius cognationis ….” This ius cognationis, Hostiensis continued: “naturale est et firmatum ex praecepto domini dicentis, Diliges proximum tuum, sicut te ipsum.”
76 Ibid.
77 Ibid. The merum imperium at Roman law represented the full magisterial power of the state, particularly over criminal matters. See Berger, Encyclopedic Dictionary of Roman Law, p. 494.
78 Hostiensis, Super Sexto Decretalibus, De homicidio voluntario, c. 1 (v. diffidatus): “[L] icitum quandoque hoc sit authoritate iuris quo ad illum cui conceditur ….”
79 Ibid.
80 Ibid.
81 The connection of Christianitas and war against the infidel is embedded deep within crusading ideology from the time of Pope Urban II. See Jean Rupp, L’idée de Chrétienté dans la pensée pontificale des origins à Innocent III (Paris, 1939), pp. 73–90. See also generally Gerhart B. Ladner, “The Concepts of Ecclesia and Christianitas and Their Relation to the Idea of Papal Plenitudo Potestatis from Gregory VII to Boniface VIII,” in Sacerdozio e regno da Gregorio VII a Bonifacio VIII (Rome, 1954), pp. 49–77.
82 See Hugh of St. Victor, De sacramentis de christianae vitae, on “De unitate Ecclesiae,” PL, vol. 176, cols 419–420. Hugh declares at one point (ibid., col. 419): “About those earthly goods pertaining to the earthly life, which prelates possess in their subjects or which subjects possess from their prelates; these goods given to the Churches of Christ by the devotion of the faithful are to be possessed; nevertheless with the right of the earthly power preserved.” (“De his autem terrenis bonis ad terrenam vitam pertinentibus, quae vel possident praelati in subjectis, vel subjectis possident a prelatis; quaedam Ecclesiis Christi devotione fidelium concessa sunt possidenda; salvo tamen jure terrenae potestatis.”) A little later Hugh adds: “The spiritual power should not so govern that it prejudices the earthly power in its right, just as the earthly power never usurps without fault that which belongs to the spiritual.” (“Spiritualis siquidem potestas non ideo praesidet ut terrenae in suo jure praejudicium faciat, sicut ipsa terrena potestas quod spirituali debetur, nunquam sine culpa usurpat.”)
83 See, for instance, the essay by Yael Katzir, “The Second Crusade and the Redefinition of Ecclesia, Christianitas, and Papal Coercive Power,” in Michael Gervers (ed.), The Second Crusade and the Cistercians (New York, 1992), pp. 3–11. Cf. Rosalio Castillo Lara, Coaccion eclesiastica y sacro romano imperio (Turin, 1956), pp. 83–115.
84 See Alfons Stickler, “De Ecclesiae Potestate Coactiva Materiali Apud Magistrum Gratianum,” Salesianum, 4 (1942): pp. 2–23, 96–119.
85 See Bernard of Clairvaux, De consideratione, bk III, I, 1; in Tractatus et Opuscula, eds J. Leclercq and H.M. Rochais (Rome, 1963), vol. 3, p. 431: “Non tu ille, de quo Propheta: ‘Et eris omnis terra possessio eius.’ [Num. 24:18]. Christus hic est, qui possessionem sibi vindicat, et iure creationis, et merito redemptionis, et dono Patris.”
86 Ibid., pp. 431–432: “Possessionem et dominium cede huic; tu curam illius habe.” Elsewhere in his work, Bernard uses the term “apostolic right” as a means of limiting the pope’s earthly pretensions. Gold and silver and other extravagant possessions, Bernard noted, belong to the pope on some other ground than apostolico iure. Ibid., pp. 417–418, bk II, VI, 10. The pope, Bernard asserts, has received not dominium, but responsibility (officium). Ibid., p. 417.
87 Ibid., p. 420, bk II, VI, 13: “Glorifica manum et brachium dextrum in faciendo vindictam in nationibus, increpationes in populis, in alligando reges eorum in compedibus et nobiles eorum in manicis ferreis.”
88 See James A. Brundage, “Holy War and the Medieval Lawyers,” in Thomas P. Murphy (ed.), The Holy War (Columbus, OH, 1974), pp. 99–140.
89 C. 23 q. 8 pr.
90 C. 23 q. 8 cc. 4–6.
91 C. 23 q. 8 cc. 7–9. Cf. James A. Brundage, Medieval Canon Law and the Crusader (Madison, WI, 1969), p. 22 (analyzing these texts).
92 C. 23 q. 8 c. 10.
93 C. 23 q. 8 c. 17.
94 See Hostiensis, Lectura (Venice, 1581), X. 5.37.5 (v. ad pugnandum).
95 Ibid.
96 Ibid.
97 Ibid.; cf. X. 5.37.5 (v. sacerdotes).
98 See Hostiensis, Summa, bk III, De voto et voti redemptione, sec. 19.
99 Ibid.: “[S]ed certe non semper debet requiri ius expressum, quia plura sunt negotia quam vocabula.” Ius here clearly means both the law and the power one can assert under the law.
100 Ibid.
101 Ibid., sec. 20.
102 Ibid., sec. 19.
103 See Innocent IV, Apparatus, X.5.37.5 (v. incitant); and Bernard of Parma, Glossa ordinaria, X.5.37.5 (v. incitant).
104 See James A. Brundage, Medieval Canon Law (London, 1995), p. 218.
105 See Brundage, “Limits of the War-Making Power,” p. 84.
106 See Giovanni da Legnano, De Bello, De Represaliis, et De Duello, ed. Thomas Erskine Holland (Washington, DC, 1917).
107 “Celestial spiritual war” was the struggle between God and Lucifer recorded in the Book of Job. Ibid., chap. III, pp. 80–81. “Earthly spiritual war” was the struggle of individuals to resist the evil attacks of the devil. Ibid., chaps VII–VIII, pp. 82–84.
108 Ibid., chap. X, pp. 85–90 (on universal war); and ibid., chap. LXXVIII, p. 130 (on particular war).
109 Ibid., chap. X, p. 85.
110 Ibid., pp. 85–86.
111 Ibid., p. 86. “[E]t tale medicamen est bellum eradicativum et extermanativum malorum.” Testing the limits of the natural right of self-defense, Legnano posed the hypothetical: may a son resist and make war against his father’s unjust commands? He answered in the affirmative: the right of self-defense arises from natural law (haec defensio provenit a iure naturali), and so outweighs a father’s paternal right (ius patriae potestatis), which, according to Roman law, arises from the civil law. Ibid., chap. XCI, p. 141. Cf. Justinian’s Institutes 1.9.
112 Ibid., chap. XII, pp. 91–93.
113 On Legnano’s arguments about the rights of non-Christians, see James Muldoon, Popes, Lawyers, and Infidels: The Church and the Non-Christian World, 1250–1550 (Philadelphia, PA, 1979), pp. 21–22.
114 Legnano, De Bello, chap. XII, pp. 92–93.
115 Ibid., chap. XVI, p. 95.
116 Ibid., chap. LXVII, p. 127.
117 Ibid., chaps XIII–XIV, pp. 93–94.
118 Ibid., chap. XIV, p. 94.
119 See Hugo Grotius, De jure belli ac pacis libri tres (Lausanne, 1751–1752), bk I, chap. III, 4.2 (jus habere belli gerendi); and bk I, chap. III, 5.1 (jur armorum movendorum).
120 Ibid., bk I, chap. III, 6.1: “Facultas ergo moralis civitatem gubernandi … Dionysius Halicarnassus tria maxime notat jus magistratuum creandorum, jus legum condendorum, et tollendorum, jus decernendi de bello ac pace.”
121 Ibid., chap. III, 4.2. It must also be noted, however, that Grotius sought to reconcile this view with the claim that the large private trading firms—such as the Dutch East India Company—which were a steady feature of the legal landscape of the early seventeenth century possessed the right, in the absence of civilly-constituted authority, to wage private war. See Charles J. Reid, Jr., “Hugo Grotius: A Case of Dubious Paternity,” The Green Bag, second series (2006): pp. 109–14.
122 See, for instance, the essays collected in Hedley Bull, Benedict Kingsbury, and Adam Roberts (eds), Hugo Grotius and International Relations (Oxford, 1990).
123 See “Text of Joint Resolution,” Washington Post, September 15, 2001, p. A4.
124 See David E. Sanger, “Bush Orders Heavy Bombers Near Afghans; Demands Bin Laden Now, Not Negotiations,” The New York Times, September 20, 2001, p. A1; Christopher S. Wren, “U.S. Advises U.N. Council More Strikes Could Come,” The New York Times, October 9, 2001, p. B5; and Steven Erlanger, “Russian Aide Warns U.S. Not to Extend War to Iraq,” The New York Times, February 4, 2002, p. A10.
125 See George P. Schultz, “Terror and the States,” Washington Post, January 26, 2002, p. A23.
126 See Sharon LaFraniere, “Vatican Says Use of Force by U.S. Can Be Justified,” The Washington Post, September 25, 2001; and “Vatican Signals Wider, Qualified Support for U.S. Military Action,” America, October 8, 2001, p. 4.
127 In a statement released December 11, 2001, the Pope endorsed the right of selfdefense but added that “[t]he recruitment of terrorists in fact is easier in situations where rights are trampled upon and injustices tolerated over a long period of time.” See Melinda Henneberger, “Pope, Not Mentioning U.S., Urges Military Restraint,” The New York Times, December 12, 2001, p. B4.