Just War Theory: A Primer


All Christians desire to fight injustice, bring about peace, and diminish the amount of pain in the fallen world we live in. Throughout history there have been differing ideas about how the Church is to achieve these goals. Many great men and women have asked what is permissible and what is inexcusable for the Church in regards to achieving these goals. Dietrich Bonhoeffer struggled greatly with this issue. He wrote about peaceful living and loving enemies but later found himself involved in a (failed) plot to kill Hitler. One idea regarding how to deal with injustice, predominantly dealing with war and violent conflicts, is called the just war theory.

The just war theory is somewhat of a mystery to many Christians even though a large number of believers would choose the stance over nonviolence/pacifism at first mention (which are really the only two viable options for any serious follower of Jesus). Just war theory attempts to conceive of how the use of arms might be restrained, made more humane, and ultimately directed towards the aim of establishing lasting peace and justice. Just war is not the process of justifying war or an excuse to support engaging in any war that one may feel is just or even unavoidable.

History of Just War Theory
Saint Augustine (354-430 A.D.) is said to be the author of what is now called the “just war theory.” Some attribute partial credit to Saint Thomas Aquinas as well. Augustine believed that Christians had no right to defend themselves from violence. He was the first theologian to question the obligation of Christian love to use violence in defending the innocent against evil. Why it took several hundred years after the resurrection of Christ for a theologian to pose this question is a mystery (especially since the Church was a nonviolent group up until around this point) but chances are it can be accredited to Augustine’s stance being developed a good time after the conversion of Emperor Constantine (d. 337). It’s also worth noting that Augustine drew his stance largely from Stoic just war principles and men who were not followers of Jesus Christ.

Many have associated just war theory with holy wars or crusades and some want to associate the theory with machismo affairs or political wars but all these associations are short-sighted as well as false. Just war theory is a severely complex ethical discipline. As theologian Stanley Hauerwas says, “If you think pacifism is a hard line, try just war theory.”

The Just War Theory
• Just war criteria presuppose that no Christian person should be involved in any war unless it meets all or at least most of the criteria.
• Just war theory assumes that initiating war is generally a crime and that only one party involved may be justified and it is most often not the aggressor. Revolutions are never considered just wars.
• People are not justified by the theory; instead their actions are relatively justified by it.
• Just war theory anticipates situations where victory cannot be gained without using indefensible means, and renounces them, accepting defeat as an honorable outcome.

The Criteria:
1. The war must have a just cause (the only permissible objective of a just war is to redress evil injury of the innocent).
2. It must be waged by a legitimate authority (even just causes cannot be served by actions taken by individuals or groups who do not constitute an authority sanctioned by whatever the society and outsiders to the society deem legitimate. Many would claim attendance of religious authority as mandatory).
3. It must be formally declared (tactics not consisting of honesty and fair warning concerning coming force prior to attack on the innocent are forbidden).
4. It must be fought with a peaceful intention (the peace established after the war must be preferable to the peace that would have prevailed if the war had not been fought).
5. It must be a last resort (all non-violent options must be completely exhausted before the use of force. Often, this is listed as the first piece of criteria).
6. There must be a reasonable hope of success (all deaths and injury incurred in a hopeless cause are not morally justifiable. This must include a probable degree of achieving whatever just goal is made necessary by point one).
7. The means used must possess proportionality to the end sought (states are prohibited from using force not necessary to attain the limited objective of addressing the injury suffered).

Three additional conditions must be met regarding the condition for the permissible conduct of war:
1. Noncombatants must be given immunity (Civilians are never permissible targets of war and every effort must be taken to avoid killing civilians. This includes the possibility of sacrificing hundreds of soldiers for the sake of one noncombatant and not dropping bombs to end a war more quickly so a greater number of people can be saved via the involuntary sacrifice of noncombatants).
2. Prisoners must be treated humanely.
3. International treaties and conventions must be honored (even if the opposing side will not submit to international treaties or conventions. The just warrior must fight justly according to all laws).

Obviously, many questions concerning the specifics of the above terms and statements remain. As a result, the just war theory is not as concrete as one would hope. If we look at the criteria under the lens of scripture and in the practice of prayer our answers to our confusion will come easier.

Some of the questions that spring from the soil of this criteria are “What must be voiced to the opposition when action is formally declared,” “what defines reasonable hope for success,” and “how can we measure the appropriate amount of force needed to obtain the limited object proposed efficiently?” More are addressed below in the category titled Just War Questions for Today.

Augustine’s Position
In the late 300’s there was no concept of “Christian” nations like today. Rome was the only state consisting of leadership that claimed to be Christian. Rome had recently altered its law drastically from outlawing the proclamation of Christ and the practice of Christ-like living to enforcing it upon all military participants. This is due to the conversion of Emperor Constantine (estimated 313). There was toleration for civilians to practice Christian living for the first time in history. In Saint Augustine’s view, Rome was upholding Gods order in the world.

Augustine maintained that Christians should fight for the sake of the Roman nation because of the Christian leadership in Rome. For him, Christians could only fight for Rome, and that was obvious, because their enemies were always enemies not only of the Roman nation, but of the peace and order Rome sought to uphold. Augustine’s interpretation of Romans 13 led him to believe that Christians had a due loyalty to Rome and thus were not only allowed to participate in military service but were obligated to do so. The Christians in Corinth and Egypt were not held to the same standard since their state was not following the right god.

Augustine was essentially attempting to formulate a system which would have allowed Christians to have a say in the operations of the one “Christian” power in the world. Augustine was not attempting to actually form what has become the “just war theory.” The theologian was never attempting to justify war (for anyone except Rome) or baptize the use of violence for the sake of Christ Jesus (except through Rome). A fair modern comparison would be Rick Warren declaring that war is unjust except when the United States is involved to uphold God’s order and that all Christians would do well to join the military.

It must be noted that Augustine’s position is not shared by those who came before him. Tatian once said “I do not wish to be king… I reject military service.” Hippolytus proclaimed, “A soldier of the civil authority must be taught not to kill men and to refuse to do so if he is commanded, and to refuse to take an oath. If he is unwilling to comply, he must be rejected for baptism. A military commander or civic magistrate who wears the purple must resign or be rejected. If an applicant or a believer seeks to become a soldier, he must be rejected, for he has despised God.” The fact that these men and their quotes predate the conversion of Emperor Constantine has no bearing on the dissonance between Augustine’s proclamations and those of his brothers of faith who clung to phrases such as, “Christians are not allowed to correct with violence” (said by Clement of Alexandria).

Despite Augustine’s difference in opinion with previous Christians concerning war and support of the state he held many similar beliefs. Augustine never supported the idea of Christians using violence in personal matters such as self-defense or to defend persons in trouble. For instance, his stance does not argue for a Christian to fight off a mugger or rapist with violence to defend the innocent victim. We must remember the context of the just war theory and not try to apply it where it was never meant to be applied.

Just War Questions for Today
It is abundantly clear (from government systems to the earth’s scientifically accepted celestial location) that the world of 2014 is not the same as the world Augustine lived in. With historical events such as Gandhi and Martin Luther King’s slow and nonviolent victories over their oppressors, one must ask the question “what does it look like to know all nonviolent means for resolution have been exhausted?” Exhausting all nonviolent means can take an immeasurable and unpredictable amount of time. How do we react within a given time limit according to just war theory? Not only that but what does exhausting all nonviolent means look like on an international scale?

Along with these questions we must also ask “what do peaceful intentions look like and how are they put into practical terms during times of international conflict?” If the opposition is bringing evil upon the innocent without violent or malicious means then how does one react according to the criteria? What forms of weaponry are permissible by the criteria? Who is authorized to answer these questions?

The Roman Catholic Church, and many other religious factions, maintain the just war theory as part of their official doctrine. Anyone who makes just war theory part of their doctrine must prescribe to the whole of theory otherwise the abandon the very framework of it. In this context we have to ask “who does the Catholic church deem as a true form of authority” (if it were solely the government of each local congregation there would be great conflict), “what constitutes humane treatment of prisoners,” and “what constitutes a truly just war?”

One of the greatest complications with just war theory is the question of “what defines an innocent victim?” This question, like many others, becomes far more complicated when put into international terms. These questions help illustrate the strictness of the theory and how the criteria severely delimit the possibilities in war for those who adhere to it.

Facts Regarding Just War Theory
“No authoritative Christian body has ever, prior to the commencement of fighting, decreed that one side, or the other is justified in warfare on the basis of just war criteria.” –Walter Wink

WWII has been almost universally regarded by the victors as a “just war.” But no church body, before or at any time during that war, examined it in the light of just war criteria. John Courtney Murray, the leading Roman Catholic interpreter of just war theory at the time, admitted that no sustained criticism of World War II was made before or during that war by Catholic ethicists. “The traditional doctrine was irrelevant during World War II.” –Walter Wink

Outside of a type of nonviolent stance, just war theory is the most conservative stance on violence and war in Christian history (when faithfully embraced). For more information on this historic and heavily debated topic check out some of the resources below.

Engaging the Powers by Walter Wink
Speak Up for Just War or Pacifism by Paul Ramsey and Stanley Hauerwas
The Moral Vision of the New Testament by Richard B. Hays
Beyond Just War and Pacifism by Gene Sharp
Christian Attitudes toward War and Peace by Roland Bainton
Principles of Just War by Vincent Ferraro
Doing Right by David W. Gill
Speak Truth to Power by the American Friends Service Committee

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