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The Church's Just War Theory - Part 1


With recent conflict between Iraq sod the United States. the the of war, the use of chemical weapons, and the debate over the morality of the embargo imposed since Desert Storm, what moral teaching guides our thinking as Catholics concerning these issues?


Before addressing the particular issues of germ warfare or other weapons of mass destruction, or of the embargo, we must first review "just war theory." At first hearing war seems antithetical to Christianity since the Fifth Commandment states, "Thou shalt not kill."

However, the intent of the precept forbids the purposeful taking of human life (Catechism, #2307). Each person has a duty to preserve his life, and therefore has a right to legitimate self defense. Although an act of self-defense may have a two-fold effect — the preservation of the person's life and the unfortunate taking of the aggressor's life — the first effect is intended while the second is not.

In preserving its own life, a state — citizens and their governments — must strive to avoid war and settle disputes peacefully and justly. Nevertheless, "governments cannot be denied the right of lawful self-defense. once all peace efforts have failed" (Vatican II, Pastoral Constitution on the Church in the Modern World, #79). Such a right does not entail a carte blanche permission for any and all acts of war. Just war theory establishes moral parameters for the declaration and waging of war.

St. Augustine (d. 430) was the originator of the just war theory, which St. Thomas Aquinas (d. 1274) later adapted and explicated in his Summa Theologiae. St. Thomas maintained that a war may be waged justly under three conditions: First, the legitimate authority who has the duty of preserving the common good must declare the war. For instance, according to our Constitution, only Congress can legitimately declare a war. A private individual, no matter how much clout he may wield, does not have the right to commit a country to war. (Please note, we could easily get into those technical qualification of "police actions," "conflicts, " and "operations, " but to the best of my knowledge, Congress has placed restrictions on these areas.)

Secondly, a just cause for war must exist. St. Augustine, quoted by St. Thomas, said, "A just war is apt to be described as bone that avenges wrongs, when a nation or state has to be punished, for defusing to mace amends for the wrongs inflected by its subjects, or to reborn what it has seized unjustly.

Finally, St. Thomas said the warring party must have the right intention, "so that they intend the advancement of good or the avoidance of evil. " St. Augustine noted, "True religion looks upon as peaceful those wars that are waged not for motives of aggrandizement or cruelty, but with the object of securing peace or punishing evil-doers, and of uplifting the good. " An evil intention, such as to destroy a race or to absorb another nation, can turn a legitimately declared war waged for just cause into a wrongful act."

Obviously, since the Middle Ages, warfare has changed dramatically, as witnessed by World War II and the conflicts which have followed it. Therefore, we can expand St. Thomas' and St. Augustine's theory to the following: In preparing to wage a just war (ius ad bellum), a country must meet the following criteria:

(1) Just cause — The war must confront an unquestioned danger. "The damage inflicted by the aggressor or the nation or community of nations must b lasting, grave and certain, assets the Catechism (#2309).

(2) Proper authority — The legitimate authority must declare the war and must be acting on behalf of the people.

(3) Right Intention — The reasons for declaring the war must actually be the objectives, not a masking of ulterior motives.

(4) Last resort — All reasonable peaceful alternatives must have been exhausted or have been deemed impractical or ineffective. The contentious parties must strive to resolve their differences peacefully before engaging in war, e.g. through negotiation, mediation, or even embargoes. Here too we see the importance of an international medial body, such as the United Nations.

(5) Proportionality —The good that is achieved by waging war must not be outweighed by the harm. What good is it to wage war if it leaves the country in total devastation with no one really being the winner? Modern means of warfare give great weight to this criterion.

(6) Probability of success — The achievement of the war's purpose must have a reasonable chance of success.

If a country can meet these criteria, then it may justly enter war. Moreover, a country could come to the assistance of another country who is not able to defend itself as long as these criteria are met.

However, the event of war does not entail that all means of waging war are licit; essentially, the "all is fair in love and war" rule is flawed. During war, the country must also meet criteria to insure justice is preserved.

(1) Discrimination — Armed forces ought to fight armed forces, and should strive not to harm non-combatants purposefully. Moreover, armed forces should not wantonly destroy the enemy's countryside, cities, or economy simply for the sake of punishment, retaliation or vengeance.

(2) Due proportion — Combatants must use only those means necessary to achieve their objectives. For example, no one needs to use nuclear missiles to settle a territorial fishing problem. Due proportion also involves mercy — towards civilians in general, towards combatants when the resistance stops (as in the case of surrender and prisoners of war), and towards all parties when the war is finished.

While these are "just criteria" — they still are wrenching. It seems paradoxical that the Christian religion which promotes love justifies a violent action to establish justice. No good peon wants war. Yet at times we — as an individual, community, or nation — must confront and stop an evil. Pope John Paul II in an address to a group of soldiers stated, "Peace, as taught by Sacred Scripture and the experience of men itself, is more than just the absence of war. And the Christian is aware that on earth a human society that is completely and always peaceful is unfortunately an utopia and that the ideologies which present it as easily attainable only nourish vain hopes. The cause of peace will not go forward by denying the possibility and the obligation to defend it."

Next week, we will continue this discussion looking at the ideas of total war and modern types of warfare.

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Saunders, Rev. William. "The Church's Just War Theory (Part 1)" Arlington Catholic Herald.

This article is reprinted with permission from Arlington Catholic Herald.

The Author

saunders1saundersFather William Saunders is pastor of Our Lady of Hope parish in Potomac Falls, Virginia. He is dean of the Notre Dame Graduate School of Christendom College. The above article is a "Straight Answers" column he wrote for the Arlington Catholic Herald. Father Saunders is the author of Straight Answers, a book based on 100 of his columns, and Straight Answers II.

Copyright © 2003 Arlington Catholic Herald

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