Onward Christian Soldiers? Just War Tradition


Michael McKenzie

Article ID:



Apr 13, 2023


Apr 20, 2009

This article first appeared in the Christian Research Journal, Fall (1996). For further information or to subscribe to the Christian Research Journal go to: http://www.equip.org/christian-research-journal/


The just war tradition (JWT) arose from a desire to have the Christian faith influence the terrible necessity of warfare. Just War Tradition allows Christians to evaluate potential conflicts and to influence other conflicts once they have begun. It also allows Christians to see God as present and active even amid the violence and destruction of warfare. Although not a settled doctrine, JWT is a consensus of Christian and secular sources, and helps Christians to practice their faith in a responsible fashion in the public square.

When Bill Clinton was stumping for the presidency in 1992, his campaign centered almost exclusively on domestic policy, distilling all issues into his famous slogan, “It’s the economy, Stupid.” Since his inauguration in 1993, however, President Clinton has spent much time on foreign policy. He has kept U.S. troops wherever his predecessors had left them; and he has sent troops into other trouble spots around the globe. Clinton has discovered the two truths that every president this century has had to learn: the promise of American isolationism is an impossible myth, and the need for active and well-trained armed forces will not go away.

What is the place of the Christian faith in all this? How can Christians evaluate whether any proposed U.S. troop commitment is justified? How can the killing of human beings be squared with the Christian faith? Are Christians left with only three choices: complete pacifism, militaristic jingoism, or withdrawal from the political/military arena altogether?

This article will examine a fourth option, just war tradition (JWT). We will see how it gives Christians an intellectual and theological matrix through which to evaluate potential and actual conflicts, as well as guidelines for how wars ought to be fought. Just War Tradition is a broad consensus, not a settled doctrine. It was developed over centuries by theologians and jurists who desired to apply Scripture and moral wisdom even to the most brutal of human enterprises, and who wanted to bring Christian charity and justice even to warfare.1 The tradition does not claim to remove all difficulties. Its broad consensus does, however, allow thoughtful people to bring their faith to bear on difficult issues in the secular political arena.


Early Christian church fathers, speaking in behalf of a minority often persecuted for their faith, were substantially of one mind in their rejection of violence in general, and of military service for believers. Tertullian (ca. 155-240) was quite adamant in his advocacy of pacifism, claiming force was entirely out of place for the Christian. He stated that not only was violence at odds with the Christian faith, but the idolatry and emperor sacrifice required of the Roman military made army service doubly prohibitive for the Christian.2 Later church fathers were not so sure.

Ambrose of Milan (ca. 339-397), the spiritual mentor of Augustine, argued that a secure peace may be won by a just war; and he insisted that the Christian faith should act to bring justice and compassion to the conduct of war.3 This attitude almost certainly reflects the new role of the church as no longer the persecuted minority but an officially recognized religion of the state. It also reflects a more thorough exegesis of Scripture that was continued in the work of Augustine (354-430).

Augustine wondered why, if rejection of military force was so crucial to one’s faith in God, men such as David, the Centurion of the Gospels (Luke 7), Cornelius (Acts 10), and the soldiers who came to John the Baptist (Luke 3) were not told to renounce their occupation, and in several cases were even held out as examples of faith. Augustine saw that Christianity was not incompatible with war, but was to influence it toward the proper methods and ends: “Peace should be the object of your desire; war should be waged only as a necessity.”4 Violence may be necessary in our fallen world to protect the innocent and to fulfill the command to love one’s neighbor.

Augustine reasoned that what had been truly evil about war was not necessarily the deaths incurred, but that part of war which had been left too long without the influence of the faith: “The real evils in war are love of violence, revengeful cruelty, fierce and implacable enmity, wild resistance, and the lust of power, and such like; and it is generally to punish these things, when force is required to inflict the punishment, that, in obedience to God or some lawful authority, good men undertake wars, when they find themselves in such a position as regards the conduct of human affairs, that right conduct requires them to act, or to make others act in this way.”5

In a world of sin, death, and misery, waging wars will always be necessary. Augustine did not doubt that this is so, but he was quick to acknowledge that these “stern and lasting necessities” were a “misery” to contemplate.6 The universality of sin insured that there would always be insatiably evil men, who, unmoved by reason or tears, made certain that wars, like the poor, would always be with us.

During the Middle Ages and beyond, jurists and theologians continued to wrestle with how moral wisdom, compassion, and justice could be brought to bear on war and conflict. As a result, several broad streams of thought — both sacred and secular — came together to form the larger context of Just War Tradition. Scholars such as the Dutch jurist Hugo Grotius (1583-1645) were responsible for bringing Just War Tradition out of a purely church context, relying on the “laws of nations” and natural law, rather than theological reasons, on which to base their conclusions.7 From traditions as varied as the early church fathers, the medieval church and knightly class, all the way to modern canon and secular lawyers, has come a surprising consensus of how just wars are to be fought.


Sending troops in harm’s way is not something to be taken lightly. When President Clinton argued that the United States had a moral duty to send 20,000 ground troops to Bosnia, many Americans were unconvinced. Despite the triumph of the Gulf War, the specter of Vietnam was brought up again and again: Would U.S. troops once again become mired in a faraway country, fighting for a cause that was unclear at best, and lost at worst? Christians were particularly unsure. Could they support the president?

Just War Tradition has developed five criteria which ought to be satisfied before troops are sent into an arena of potential conflict.8 Called the jus ad bellum (justice for war), these criteria serve to frame the discussion surrounding any potential war.

Just Cause. Wars designed for aggression against a neighbor, or those designed simply to increase a country’s wealth or prestige cannot be justified. A just cause may be to intervene on behalf of an innocent third party, to punish an evil or aggressor nation, or to defend one’s own nation against aggression or overthrow.9

Right Authority. This category is designed to insure that the proper authorities are calling for the war. Just wars are not private revolutions. In the United States, the Congress has the power to declare war, thereby helping to ensure that there will be vigorous debate before the wholesale commitment of American ground forces.

Proportionality. Any potential conflict must be evaluated as to the cost and benefits. Are the potential gains worth the possible costs and sacrifice — both with regard to finances and human lives? Will the destructiveness of the proposed conflict outweigh any enhancement of other human values? Clearly, this category requires foresight; the difficulties involved do not absolve a country from this responsibility.10 For example, there is more risk involved in committing ground troops than in utilizing air strikes. Is the risk of getting mired in a ground war worth the cost? As the Union troops in the Civil War battle for Fredericksburg found out, getting in may prove much harder than getting out.

The Goal of Peace. This criterion requires that just wars be fought with the final, realizable goal of peace in mind. Not only should there be a strategy to win; there should be a peace that can be achieved. It was this element that disturbed many Americans about the committing of U.S. ground troops to the conflict in Bosnia. They wondered if any “simple” one-year commitment of U.S. troops could do anything to bring a lasting peace to a conflict that had lasted centuries.

War as the Last Resort. Nonviolent means of persuasion should always be attempted for a reasonable amount of time before resorting to war. In the modern political climate, there are numerous means that can serve to achieve the desired end of peace: diplomacy, economic boycotts, and other tactics have all worked to achieve just ends. But, there are times when diplomacy fails. The “last resort” implies that the use of force may be legitimate.


Once a decision has been reached that war is unavoidable, how should a nation conduct itself in warfare? Keeping in mind that wars are always “neater” on paper than in the field, Just War Tradition nevertheless has two important criteria that keep the violence of war from escalating into total mindless savagery. These criteria for jus in bello (justice in battle) are proportionality and noncombatant immunity.

Proportionality. In conducting a battle just as much as in determining to enter a war, likely goods must be weighed against likely evils. For example, in various campaigns in the South Pacific during World War II, Japanese-held islands were often bypassed and left “to wither on the vine” rather than be invaded. The cost in human lives was simply not worth any potential benefits. This was an example of proportionality in action.

Modern-day “smart weapons” are a huge advance over the weapons of 50 years ago, and can help in keeping violence proportional. As the Gulf War demonstrated, it is often possible to destroy a military target with a comparatively small load of explosives because of the pinpoint accuracy of the weapon. Not only does this advance in accuracy meet proportional goals, but it also provides better protection for civilians.

Noncombatant Immunity. This criterion requires that civilians not be directly and intentionally targeted. While it is true that wars inevitably kill some civilians, such killing must be an unintended and indirect product of attacks on the military.

Modern-day terrorists and guerrilla fighters pose grave threats to the doctrine of noncombatant immunity. Intentionally locating their command headquarters or military targets within civilian areas, these groups use civilians as human shields for their acts of terror. Ironically, when they hide behind civilians in this way, terrorists are paying those nations that adhere to JWT a compliment, acknowledging that such nations do not make it a practice to kill civilians intentionally. Saddam Hussein repeatedly hid military targets in the middle of residential neighborhoods. Tomahawk Cruise missiles, however, often proved more than a match for such tactics, flying around hospitals and schools in order to destroy legitimate targets.


There is nothing like warfare to reveal what is in the heart of man. As Joshua Lawrence Chamberlain, hero of the Battle of Gettysburg, said, “War makes bad men worse and good men better.”11 War also reveals the driving philosophy of the nations fighting the conflict.

During the early years of World War II, the Japanese plane most feared by allied pilots was the Zero. Nimble, quick, tight-turning, the Zero was a scourge for the Americans and British who faced it. But the plane’s agility came at a price. The Japanese government constructed the plane of paper-thin aluminum, with neither armor for the pilot nor self-sealing gas tanks — the Japanese were willing to sacrifice such pilot protection to make a lighter plane. Later on, such calculations came back to haunt them. American Air Corps P-38 Lightnings and Navy Corsairs — both heavily armored — could take massive punishment and then turn the Zeros into fireballs. In addition, the Japanese pilots often were not provided with parachutes. Such “luxuries” were thought to disgrace the warrior code of Bushido. Neglecting the most basic measures of safety for one’s own pilots was flouting the spirit of JWT.

This disregard for the individual was also characteristic of the Soviet Union during World War II. General Dwight (Ike) Eisenhower was astonished when the Soviet commander, Marshal Zhukov, related the Soviet “strategy” for clearing a minefield: “Our infantry attacks exactly as if it were not there.”12 This tactic of using men as human fodder later caused Ike to remark dryly: “I had a vivid picture of what would happen to any American or British commander if he pursued such tactics.”13 The Russians cared little about individual human lives, but only, as Ike put it, “for the overall drain on the nation.”14

An even more horrible example of Soviet indifference toward suffering in war was their attitude toward their own men who had been captured by the Germans. Zhukov expressed disbelief that the United States fed German prisoners the same rations as American G.I.’s. When Ike explained that it was best to treat German prisoners well because of the Geneva standards of decency and because ill-treatment would doubtlessly inspire Hitler to treat Allied prisoners even more harshly, Zhukov was astounded: “Why do you care about men the Germans have captured? They have surrendered and cannot fight any more.”15 In other words, once a Russian soldier had been captured, he was of no further use to “the Motherland.” Such callousness was in flagrant disregard of just war traditions of prisoner treatment and human decency. As Chamberlain might remind us, “Evil men had become worse.”


On July 31, 1943, Roger Young was pinned down with the rest of his reconnaissance patrol by a Japanese machine gun on New Georgia, one of the Solomon Islands.16 The cleverly laid ambush had already killed four soldiers and, since there was virtually no hope of rescue, it appeared that the rest of the patrol would soon be cut to pieces. Young, who had recently requested a demotion to private because he was losing his hearing, began to inch forward toward the machine gun nest. His lieutenant barked at him to stay put. Young kept going, jerking himself out of the officer’s grasp. He soon came under withering fire that nearly cut off his legs. In extreme agony, Young kept crawling within five yards of the machine gun, where he found a small depression that sheltered him from the rain of bullets. With his last gasp of strength, Young pulled out a grenade, then reared up and back, bringing himself out of the protection of the ground. A blast of machine gun fire caught him full in the face, killing him just as he released the grenade. But his aim was true. The grenade landed squarely in the middle of the machine gun nest, killing every enemy soldier. The thin, pale, bespectacled Young had saved his patrol.

On February 7, 1943, submarine skipper Howard Gilmore was on routine patrol in the South Pacific. After ramming a Japanese ship, his submarine suffered heavy damage and was being destroyed by the ship’s machine gun fire. Two seamen were killed and Gilmore was badly wounded on the conning (observation) tower. Unable to make it to the hatch, Gilmore did the only thing he thought he could to save his crew. Despite the protests of his officers and crew, he ordered the sub to dive, leaving himself to die on the surface. Howard Gilmore had died in order to save his 69 men.17

Young and Gilmore both received the Congressional Medal of Honor, America’s highest military honor. Criteria for the Medal are “unquestionably strict.” The act in question must be reported by at least two eyewitnesses, distinguishable above other acts of gallantry, and involve the risk of one’s own life. In fact, nearly two of every three men who so far have received the medal did not live to see their award.18 According to a revered military custom, every officer — generals included — must rise and salute any winner of the Medal. The salute shows the endearing respect for “the man, the medal, the deed.”19

But why do we respect such heroism and self-sacrifice? Why is it so moving to read the story of a Roger Young or a Howard Gilmore? I believe that God’s creating humanity in His image includes a connection between that image and the ultimate act of giving one’s life. We respect such courage because we know that to give all one has, to give all that a person holds dear in this world, is to act outside oneself. It is a pointer, however humanly expressed, toward God, who expressed Himself in the ultimate act of self-sacrifice on Calvary. This is a courage that transcends even the horrible carnage of war.

Jesus said, “Greater love [agape] has no one than this, that one lay down his life for his friends” (John 15:13). The Lord is speaking in the immediate context of His own coming death on the cross. But there is no need to restrict His saying to that context. Jesus is pointing out that self-sacrifice is the indication of agape in action. His own sacrifice would be the ultimate fulfillment of that.

Paul’s comments in Romans 5:7 likewise point to the connection between agape and self-sacrifice. In the Greek text, there is an insertion that Paul seemingly added to admit that men do indeed sometimes “die for a good man.” Paul’s main point is to compare that sort of self-sacrifice with Christ, who died for us “while we were yet sinners” (5:8). The apostle uplifts Christ’s death not to disparage the human sacrifice, but to point out the greatness of the divine sacrifice: the dying and agape occurred while we were opposed to God.

Human awe in the face of bravery is nearly universal. Despite the killing, the terror, the horror of war, there can emerge an inexplicable, yet undeniable, transcendence. This transcendence is not simply a function of zealous patriotism. Rather, it remains a pointer to the God whom even stark tragedy cannot drive away. It is also, at the very least, an acknowledgment of God’s providence. “Fighting and destruction are terrible,” wrote Joshua Lawrence Chamberlain, “but are sometimes agencies of heavenly rather than hellish powers.”20


Several contemporary issues pose special problems for JWT. The likelihood is that terrorists and guerrillas will continue to press the limits of noncombatant immunity, threatening to bring as many people as possible into the circle of war in order to achieve their ends. Such concerns are particularly significant in light of the collapse of the former Soviet Union, the internal discord within the various former Soviet republics, and the danger of “black-market” sales of nuclear weapons. Any country that desires to adhere to Just War Tradition must not return terror for terror. Instead, despite temptations to the contrary, it must strive as much as possible to adhere to the jus in bello criterion of noncombatant immunity.

Other moral concerns involve nuclear weapons themselves. Not long after the destruction of Hiroshima in 1945, debate began on the morality of nuclear weapons. Such debate has focused on two main issues that are seen by some to overturn the concept of just war altogether: the enormous power of nuclear weapons and the strategies employed by the nuclear powers to prevent war (deterrence).

Some scholars are convinced that the tremendous destructive capacity of nuclear weapons places them entirely outside the scope of JWT. They are simply too destructive, too powerful to categorize in the traditional categories of jus in bello.21 Yet, there has been a significant progress in nuclear weapons technology. To cite just one example, “miniaturized fusion bombs” (commonly called “neutron bombs”) can now be delivered to military targets with far less collateral damage and long-term radiation effects.22 These developments in so-called “smart weaponry” should be viewed as significant moral improvements over strategies such as delivering megatonnage bombs over general, less specific targets. Thus, advancement in military technology toward greater accuracy and precision has given the U.S. an opportunity to shift its strategic emphasis from general targets with large civilian populations where accuracy wasn’t needed to specific, detailed military targets where accuracy is at a premium.

Some argue that nuclear weapons are so destructive that even their nonuse is immoral. Such thinkers are convinced that their awful destructive capacity, combined with the immoral nuclear deterrent doctrine of “mutually assured destruction,” insures that even the threat to use such weapons is wrong. How can it be moral to threaten to destroy another country’s cities after one’s own country has been leveled?23

Such arguments, however, are directed at the policy of “counter-city” nuclear attack, complete with inaccurate, megatonnage nuclear weapons delivered over or near cities, insuring that civilian deaths would be disproportionate. Because of the evolution of weapons technology, targeting doctrine is now likewise open to evolve in the direction of “counter-force.” The JWT would welcome such a change. In the past decade, the accuracy of weapons delivery systems has improved to the extent that it is now possible to reduce the size of the warhead. Because of this increase in accuracy, it may even be possible at times to substitute conventional warheads for nuclear, thus eliminating the danger of radiation.24 It also must be acknowledged that nuclear weapons do deter. During the Gulf War, one of the biggest concerns of both the American military intelligence and the general public, was that Saddam Hussein would unleash his biological and chemical arsenal upon American soldiers. He had shown in the past against the Kurds that he had no qualms about using such weapons, and many people were fearful that he would do the same in Kuwait against American troops and in Scud missiles fired into Israel. It turned out that the only reason he did not was that he feared a nuclear retaliation by either Israel or the United States. According to General Wafic Al Samar‘ai, the then military advisor to Hussein and former chief of Iraqi military intelligence, “Some of the Scud missiles were loaded with chemical warheads, but they were not used. . . . We didn’t use them because the other side had a deterrent force.”25 In my opinion there is a legitimate place for nuclear deterrence in modern Just War Tradition, but it should avail itself of every proven advance that allows nuclear deterrent to be focused on military, not civilian, targets. (This is not to deny the importance of negotiations among nations that result in reductions in nuclear arsenals and nuclear test ban treaties. However, since such negotiations are not directly a part of JWT, I have not expounded on them in this article.)

If nuclear weapons are the crisis of the wealthier powers, then the epidemic of military mines is the crisis of poorer nations. The criteria of jus in bello dictate, “Weapons of war should be, by design, highly controllable and relatively limited in their destructive effects.”26 The eight to ten million mines still buried in Cambodia, on the other hand, are primarily designed to injure horribly whoever might stumble onto them.27 And since their destructive power can last for a century or more, hundreds and thousands of civilians will be maimed and killed long after the related conflicts are forgotten.

Mines have traditionally been used to block or slow military advances, halt enemy infiltration, or help protect defensive positions. In southeast Asia, however, mines are often scattered anonymously with no regard for marking their location or for any military purpose. Hidden in agricultural or residential areas, those mines are used primarily to cause terror among the civilian population.28

Military technology has not been of much help in reducing this horror. So-called “smart mines,” designed to self-destruct after a certain amount of time in the ground, have a 10 to 20 percent failure rate, insuring that live mines will remain a danger long after the war is over. Additionally, most of the mines do not come from countries that have manufactured smart weapons and are too primitive to self-destruct.29

Although JWT can support a regulated use of land mines in military operations, Christians and other thoughtful people have a responsibility to support legislation that attempts to place international controls and restrictions on the manufacture, sale, and use of land mines. The maiming and killing of civilians — men, women, and children — is continuing at a horrific pace in southeast Asia. Such atrocities fly in the face of the just war tradition.


Christians have long recognized that they hold dual citizenship. As citizens of the kingdom of God and ambassadors of Christ, they strive to let their light shine everywhere (Matt. 5:16). JWT is an invaluable moral matrix for Christians so that their faith may influence even the most horrible of humanity’s enterprises. Given the intractability of sin, Jesus says that wars will be with us until He returns (Matt. 24:7). To ignore that fact is to ignore reality. To ignore our moral responsibility is to invite conflicts to continue without the mediating influence of thoughtful Christians. The just war tradition provides no easy answers, but it can help to mediate Christ’s grace in a fallen and tragic world.

Michael McKenzie teaches in the Seattle area and is a frequent contributor to the Journal.


  1. See the excellent discussion of the background of the JWT in James Turner Johnson’s Can Modern War Be Just? (New Haven: Yale University Press, 1984), 12-16.
  2. See Arthur F. Holmes, ed., War and Christian Ethics (Grand Rapids: Baker Book House, 1975), 37-47.
  3. Ibid., 55.
  4. Ibid., 62-63.
  5. Ibid., 64.
  6. Ibid., 71.
  7. Johnson, 12-16.
  8. See the discussion of these categories in Johnson, 18-29.
  9. Ibid., 19.
  10. Ibid., 25.
  11. Joshua Lawrence Chamberlain, The Passing of the Armies (New York: Bantam Books, 1993 edition of the 1915 Putnam book), 295.
  12. Dwight Eisenhower, Crusade in Europe (Garden City, NJ: Doubleday & Company, 1948), 468.
  13. Ibid.
  14. Ibid.
  15. Ibid., 469.
  16. The entire Roger Young story appears in World War II 8, no. 4, 66-72.
  17. Medal of Honor: True Stories of America’s Greatest War Heroes (Washington, D.C.: U.S. News & World Report, 1991), 22.
  18. Ibid., 5.
  19. Ibid.
  20. Chamberlain, 295.
  21. Such is the opinion of many of the writers in Todd Whitmore, ed., Ethics in the Nuclear Age: Strategy, Religious Studies, and the Churches (Dallas: Southern Methodist Press, 1989).
  22. See James Turner Johnson’s essay in Ethics in the Nuclear Age, especially 108-9.
  23. Such is the position, for example, of John Howard Yoder in Ethics in the Nuclear Age (79-92).
  24. See Johnson, Ethics in the Nuclear Age, 113.
  25. Transcript of Frontline, 9 January 1996 (Denver: Journal Graphics, 1996), 19. United Nations Inspector David Kay agrees: “I think the Iraqis were genuinely afraid that if they used biological or chemical weapons, the United States — or if not the United States, the Israelis — would reply with nuclear weapons. And it was really the deterrent power of U.S. weapons, primarily, that prevented the use of it.” See transcript of CBS Reports: The Gulf War + 5, 18 January 1996 (Livingston, N.J.: Burrell’s Information Services, 1996), 12.
  26. Johnson, Ethics in the Nuclear Age, 110.
  27. It is actually estimated that there are nearly 100 million armed land mines in over 60 countries. See transcript of Terror in the Minefields, aired on Nova, 9 January 1996 (Denver: Journal Graphics, 1996), 1.
  28. See Terror in the Minefields, 6.
  29. Ibid., 3.
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