Fighting, killing, making war. Human beings have been doing it almost from the very beginning and show no signs of an inclination to cease and desist. Many claim that the Christian tradition is ambivalent when it comes to prosecuting wars, even in a just cause—and this, so it is alleged, because the founder of Christianity rejected all use of force. Jesus of course did acknowledge that the authority to use force came from his Father (John 19:11), but it must be admitted that, unlike the founder of Islam, the founder of Christianity did not use a sword.
For a variety of reasons (mainly focusing on the idea that Jesus’ rejection of force was meant to be unique to him rather than emulated by his followers), Jesus’ refusal of the sword did not keep Christians from employing it in increasing numbers, beginning sometime around the end of the second century. Nor did Jesus’ refusal prevent some early Church Fathers from defending the use of force. Clement of Alexandria, Eusebius, Ambrose, and Augustine, to name just four, defended the just use of force unequivocally. Their various “defenses”—especially Augustine’s—were the genesis of the Christian Just War doctrine, a doctrine which insists that war can be the sort of thing Christians ought to support. None of these early Christian approaches to war treated it as a necessary evil. Each held that the person who used just force was acting in a way consonant with God’s wishes and was, though in a way less praiseworthy than bishops and clerics, following Christ. The just soldier’s acts in war were thus thought to be positively good acts—acts that would shape him into the kind of person fit for beatitude with God. But this moral approach to war is not much favored today. Few of our contemporaries wish to claim that God elevates soldiers through their virtuous acts on the battlefield. The idea strikes many of us as morally grotesque.
There are two main reasons why many Christians today wish to disown the tradition’s acceptance of warfare as a potential good. They derive from strains of thought that have seeped into the Christian conscience and inform many modern Christian attitudes toward war. First, there is the influence of Christian pacifism. The complaint from this quarter is that one cannot follow Jesus—and thus cannot be a Christian in the fullest sense (if in any sense at all)—unless one rejects all recourse to the use of force. Christians on this view should follow the lead of the early Church, which, we are told, rejected the use of force, at least until the “Constantinian Fall” that supposedly ushered in the age of Christian imperialism. The second reason many contemporary Christians have rejected recourse to violence is that liberal-humanist ideas have convinced them that war is something inhuman, unreasoned, and unpurposeful. It is thus also something inherently ignoble, unworthy of human nature, and out of step with contemporary mores and the direction of history.
This new view of war is all around us. The recent controversy over Senator Bob Kerrey’s activities in Vietnam is a good example. Senator Kerrey received the Bronze Star for actions that have come under scrutiny of late. Apparently Senator Kerrey, while on active service in Vietnam, led a raid in which many civilians were killed. Kerrey insists that the attack on civilians was unintentional and I have no reason to dispute him. In any event, Kerrey received a medal for his work. He also received the Medal of Honor for a different action. Kerrey has stated that he deserves neither. Perhaps he is right, but he does not stop at that. He maintains that medals are given out in war in order to “clean the war up”—to make us feel good about something we should never feel good about. Kerrey’s comments are typical of the modern ethos of war: war may be necessary, but it is inherently base and vile, and it taints everything it touches. The medals, Kerrey suggests, are one way we hide this unpleasant reality from ourselves.
The modern ethos of war was first articulated by Erasmus, who argued at length that war was unnatural and unfitting for human beings, and that even just wars are morally unacceptable. But this ethos really began to gain ground during the Enlightenment, when philosophers began to argue in earnest that warfare was unworthy of civilization and even antithetical to good government. Add to these arguments the impersonal nature of mechanized warfare, the terrible, brutal nature of World War I trench warfare, the use of saturation bombing during World War II, and the debacle of the Vietnam conflict, and the result is a virtual consensus that war cannot possibly be a noble activity, much less an activity in conformity with following Christ. Indeed, the inglorious nature of modern combat led Protestant theologian Karl Barth to comment with approval that warfare had finally been “stripped of the veneer” of glory and nobility in which it had been cloaked in premodern times.
In his great Church Dogmatics , Barth treated war as an ultima ratio—something, therefore, that is barely human and surely not anything that could be called noble or virtuous. Nor is this sort of thinking confined to Protestants. Catholic moral theologian Charles Curran, for example, once worried in a debate with Paul Ramsey—a noted champion of the Christian Just War doctrine—that Ramsey did not take seriously enough the fact that war must be an ultima ratio. Curran feared that Ramsey thought war a reasonable form of human activity (which he did). The worry for Curran—as it is for many like-minded thinkers–is that we might be more likely to fight a war if we believe war can be reasonable. Curran also worried that Ramsey did not understand the realities of war because he did not spend a lot of time discussing the “horrors of war.” “One can read all his [Ramsey’s] writings on war,” Curran wrote, “without having any impression of the horrors involved in modern warfare.” Curran finds the horrors of war to be the most important thing, ethically speaking, about them.
On one level, Curran is, of course, on the right track. War is not to be entered into lightly—especially modern war with its propensity for disproportionate measures in combat. Nor is it a bad thing to want nations to refrain from going to war with little provocation, as, for instance, certain Italian city-states were wont to do in the sixteenth century. On another level, however, Curran is misguided. There is no reason to assume, for example, that simply because we believe that war can be a purposeful and reasoned activity that we will be inclined to engage in it too easily. In fact, defenders of Christian Just War doctrine typically argue that we ought to be reluctant to fight wars that lack sufficient moral and rational justification. Defenders of the Just War tradition regret that they live in a world where they have to kill human beings in order to restrain evil; that is to say, they regret the Fall. But they find it to be even more regretful for Christians to stand idly by while people are being abused and killed unjustly.
Despite the dominant view of war as something inherently ignoble and incompatible with Christian living, most Christians still approve of wars from time to time, deeming them “necessary evils.” This is not necessarily a contradiction, though it is a paradox. Popular opinion on the matter tells us that resorting to force in certain situations is “necessary” to save the lives of victims of injustice (including ourselves). Yet such actions are also held to be “evil” because warlike acts are “inhuman” and do not follow the model of Christian living found in the life of Jesus.
One way of describing this kind of moral thinking is to call it “dirty hands” morality. The thought here is that we cannot both follow Jesus in living nonviolently and be “responsible” citizens at the same time, so we go ahead and behave “responsibly” (i.e., we use force), but we admit that in doing so we get our hands dirty, which calls for repentance. There is no such thing, in this view, as a warlike act that does not demand repentance. So, we commit sinful acts when we use force, even when it is employed for the sake of just ends. Thus warfare is viewed not as a possible positive good but as a necessary evil that taints all who touch it.
There is an additional reason why the bulk of the Christian laity accepts the modern ethos of war: their leaders have bought into it. We see evidence of both pacifism and liberal humanism influencing official Church documents on war in the twentieth century, both Protestant and Catholic. A typical example is the World Council of Churches’ 1958 document “Christians and the Prevention of War in the Atomic Age.” The WCC rejects war as a potential good and renounces all war as incompatible with Christianity. Nevertheless, a particular war may be a “necessary evil””necessary either to protect some good or, best of all, to banish war altogether. But such a “necessary” war will not be a “just” war. When we say that we will allow an evil deed (such as fighting a war) in order to end a greater evil (such as the murderous policies of a tyrannical government), the former is not transformed into an act of justice. It is certainly a permissible act, but it is not a just one. On this view, then, there can be no “just” wars.
More recent examples of this thinking can be found in the pastoral letters on war offered by U.S. bishops, both Catholic and Methodist (The Challenge of Peace  and In Defense of Creation , respectively). In both pastorals, the bishops assume that just war theory and pacifism share equal status in the tradition and that pacifism ought to inform just war thinking. Indeed, the bishops would agree with Christian pacifist Stanley Hauerwas, who has written that “Christians created just war reflection because of their nonviolent convictions” (a cursory glance at the Church Fathers mentioned above belies this claim). The trouble is that the bishops, like Hauerwas, cannot figure out a way to make the military profession compatible with the life of Christ. Is it any wonder, then, that the laity have so much trouble trying to follow the teaching of the bishops? This has not always been the case. The tradition, both Catholic and Protestant, possesses figures who have taught a very different approach to the morality of warfare.
When Thomas Aquinas discusses just war in the Summa Theologiae (II-II.40), he does not do so in the section on justice, but rather in the section on charity—specifically, the love of God. He makes it clear that war is not a vice that is opposed to the love of God. On the contrary, war-making, when just, can be a form of love. Of course, war is always contrary to peace, but this is sometimes desirable, since peace is not always a just order that deserves to be preserved. Nazi Germany, for example, provided peace and order for most of those in conquered countries who were willing to accept Nazi rule. But no one wishes to argue that the peace provided by Nazis is the sort of peace we ought to preserve. War, for Aquinas, can be a means to a just peace as well as a means to destroy an unjust peace (such as one established by Nazis). We keep a just peace and fight just wars because these are acts of charity. Just soldiering, in other words, is something Christians ought to do out of love for God and neighbor, and thus it is the most “human” thing we can do in certain circumstances.
But if Aquinas believes that fighting a just war justly is a meritorious act, he also diverges from the modern presumption against the use of force that can be found in many recent moral approaches to war. Stanley Hauerwas, for example, has argued that Christian just war advocates and pacifists share a presumption against acts of force and that this presumption actually generates the just war criteria (the aforementioned bishops seem to be in full accord with him on this). Such a presumption cannot be found in Aquinas, nor can it be found in Calvin (nor, we might add, in Ambrose, Augustine, or Luther). A few quotations will suffice to prove the point. When Aquinas discusses the New Law and its relationship to the Old Law, he says “the intention of the [Old] Law was that retaliation should be sought out of the love of justice . . . and this remains still in the New Law.” Moreover, in his discussion of Paul’s advice to the Romans concerning the governing authorities (Romans 13:1-7), Aquinas insists that it is not merely allowable but positively “meritorious for princes to exercise vindication of justice with zeal against evil people.” We also find Aquinas arguing that it is both “praiseworthy and advantageous” for someone in proper authority to kill a person dangerous to the community. When we look at these claims, surely we must say that the presumption is not against force but against injustice. More importantly, on this view, charity does not merely allow for violent action, but even demands it in certain circumstances.
Calvin, too, looks at the soldier as an agent of God’s love. As he argues: “Paul meant to refer the precept of respecting power of magistrates to the law of love.” The soldier is thus as much an agent of God’s love as he is of God’s wrath, for the two characteristics are harmonious in God. Calvin argues in this way because he holds that to soldier justly—to restrain evil out of love for neighbor—is a God-like act. It is God-like because God restrains evil out of love for His creatures. None of this is to say that we fully imitate God or Christ when we use force justly, for the just soldier’s acts can never be redemptive acts—acts that have a saving quality for those who are targets of the acts of force (except, of course, in the sense that the just soldier “saves” the unjust neighbor from more unjust acts). Yet the just soldier who cultivates the military virtues in such a way as to harness and direct them toward his final end—beatitude with God—may nevertheless be said to be one who, as the Reformers liked to say, follows Christ at a distance.
The military virtues looked upon so fondly by Aquinas and Calvin are greatly frowned upon today. Few think of soldiering as an honorable and noble occupation—not even the U.S. Army, or so it seems. Indeed, one would never guess from today’s recruiting commercials that the whole point of being in the military is to use—or believably be prepared to use—lethal force as effectively as possible. Catchy slogans (“Be All You Can Be” and “An Army of One”) promise the development of abilities that become useful only after a person’s time in the military is over. The prospective soldier’s opportunity to serve his country is downplayed, presumably because the military does not want to remind people that military service can involve fighting, dying, and killing for one’s country. It is as if the Armed Forces are ashamed to admit that they are in the business of using—or threatening to use—lethal force. Senator Kerrey surely captured this aspect of military service when he remarked that he was sent to Vietnam “not to hand out leaflets” but “to kill people.”
How can we follow Christ—even at a distance—while fighting and killing? Calvin gives us an indication by pointing out that Christ’s pacific nature (his willingness to suffer violence at the hands of Jewish and Roman authorities) is grounded in the priestly office of reconciliation and intercession that is reserved for him alone. Christ’s pacific nature is thus inextricably tied to his role as redeemer and cannot be intended as a model for Christian behavior. No Christian can or should try to act as a redeemer, but all can and should follow Christ in obeying the commands of the Father. And the Father commands the just use of force.
Calvin is not alone in this way of thinking. Aquinas, for example, distinguished between those who follow the “counsels of perfection”—bishops and clerics—and those who do not. According to Aquinas, bishops and clerics cannot be soldiers because these occupations cannot “be fittingly exercised at the same time.” Aquinas offers two reasons why. First, warlike pursuits keep clergy from their proper duties. In other words, their participation is unlawful, not because war is evil, but because warlike pursuits prevent them from doing their jobs. Second, it is “unbecoming” for those who give the Eucharist to shed blood, even if they do so without sin (i.e., in a just war). Unlike Calvin, then, Aquinas finds the duties of clergy to be more meritorious than the duties of soldiers. However, this does not mean that, in Aquinas’ view, the soldier’s duties have no merit. Rather, he employs an analogy to make quite the opposite point: it is meritorious to marry but better still to remain a virgin and thus dedicate yourself wholly to spiritual concerns. Likewise, it is meritorious to fight just wars and restrain evil as a soldier, but more meritorious still to serve as a bishop who provides the Eucharist to the faithful.
Clergy nevertheless ought to offer spiritual help to the military. Aquinas insists that “among the faithful carnal wars should be considered as having for their end the divine spiritual good to which clerics are deputed. Wherefore it is the duty of clerics to dispose and counsel other men to engage in just wars.” Aquinas also approves of prayers that ask God to inflict temporal ills on enemies and insists that it is the duty of clerics to urge and counsel others to engage in just wars. He even argues that it would be acceptable to found a religious order for the purpose of soldiering. Such an order could not be established for any worldly purpose, but would instead have to fight for the defense of divine worship, as well as to ensure public safety and protect the poor and oppressed. Aquinas clearly does not seek to keep those who follow the “counsels of perfection” from involvement in military matters, but rather makes it a duty for them to participate in just war-making.
As noted above, many of our contemporaries worry that viewing warfare as a positive good will incline us to fight wars. But this is simply not the case. The tradition has always demanded that the criteria known as the jus ad bellum be met before Christians can give consent to a proposed war. Aquinas writes of three such requirements: right authority, just cause, and right intention. A lawful sovereign fits the bill for the first. As for the second and third, he quotes lists from Augustine on sufficient provocations for waging a just war: avenging wrongs, punishing a nation, and restoring what has been unjustly seized are included as just causes, while securing peace, punishing evildoers, and uplifting the good are said to be signs of right intention. These sensible criteria regarding when to fight remain useful for Christians in any era.
The issue of how we fight is another matter. Aquinas himself offers little guidance regarding the proper rules for fighting (called jus in bello). Nevertheless, we can extrapolate a handful of guidelines from his writings. For one thing, we can presume that we should fight with the right intention, that is, we must intend to punish not just anyone, but only evildoers. Likewise, we should do our best to see that our use of force does not detract from our duty to uphold the good. Of course, the ability to target only those who deserve to be punished, no less than the capacity to formulate plans of action that will issue in more good than evil, must be cultivated. Thus, for Aquinas, right conduct in war is dependent upon the virtues of soldiers and the commanders who lead them.
Unlike Aquinas, Calvin has little to say about the requirements for a just war, but he does insist that the lawful sovereign has a duty to take up arms to defend the commonwealth against those who attack it (Institutes IV.20). Calvin also insists that wars should not be waged in anger, nor in order to vent passions on others. It is a sign that we have fallen short of beatitude when our passions lead us to use force unjustly. This is why Calvin argues that princes should go to war only when driven to it by necessity and out of concern for the public good. Lastly, because soldiering is conceived as an office of love, Calvin rejects outright mercenary soldiering (a popular profession among the Swiss of Calvin’s time), since it encourages soldiers to fight merely out of love of money and not out of love for their neighbors. For Calvin, soldiering loses its Christian function and legitimacy when it becomes a commodity.
The moral approach to war in Aquinas and Calvin is refreshing for those familiar with modern Christian approaches to warfare—approaches which, more often than not, do little to help Christians understand why they should be prepared to participate in or support war of any kind. Aquinas and Calvin, in contrast, teach Christian soldiers why they need to participate in and support just wars. From the divine point of view, God desires to restrain evil among His creatures. And in using human beings to do so, God actually elevates the restrainers (if they are just soldiers who fight for love of God and neighbor) to a closer relationship with Him through their acts of force. In other words, just soldiers fight on the path of sanctification in preparation for beatitude with God. From the human point of view, the virtue of charity (the love of God) drives just soldiers to do all they can to restrain evil—to see that justice is done—and this sometimes means using force.
This strikes a discordant note among many. How, we are asked, can an act of force be loving? The short answer is that force becomes an act of love when it seeks to resemble God’s use of force. In practice this means, among other things, that acts of force must never involve intrinsic evil (such as intentionally killing innocent people, for instance).
The most noteworthy aspect of the moral approach to warfare in Aquinas and Calvin is that it teaches—contrary to today’s prevailing views—that a failure to engage in a just war is a failure of virtue, a failure to act well. An odd corollary of this conclusion is that it is a greater evil for Christians to fail to wage a just war than it is for unbelievers. When an unbeliever fails to go to war, the cause may be a lack of courage, prudence, or justice. He may be a coward or simply indifferent to evil. These are failures of natural moral virtue. When Christians (at least in the tradition of Aquinas and Calvin) fail to engage in just war, it may involve all of these natural failures as well, but it will also, and more significantly, involve a failure of charity. The Christian who fails to use force to aid his neighbor when prudence dictates that force is the best way to render that aid is an uncharitable Christian. Hence, Christians who willingly and knowingly refuse to engage in a just war do a vicious thing: they fail to show love toward their neighbor as well as toward God.
Darrell Cole, a new contributor, is a Visiting Instructor in Religion at the College of William and Mary.
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