Just war theory(jus bellum iustum) is adoctrine, also referred to as atradition, ofmilitary ethicsstudied bytheologians,ethicists,policy makers, and military leaders. The purpose of the doctrine is to ensure war is morally justifiable through a series ofcriteria, all of which must be met for a war to be considered just. The criteria are split into two groups:"the right to go to war' (jus ad bellum)and'right conduct in war' (jus in bello). The first concerns the morality of going to war and the second with moral conduct within war.[1]Recently there have been calls for the inclusion of a third category of just war theory - jus post bellum - dealing with the morality of post-war settlement and reconstruction.

Just War theory postulates that war, while very terrible, is not always the worst option. There may be responsibilities so important, atrocities that can be prevented or outcomes so undesirable they justify war.[2]Contents

[hide] 1Origins 1.1Saint Augustine 1.2Thomas Aquinas 1.3School of Salamanca 1.4Just War Doctrine 1.5Formally described Just War 2Criteria of Just War theory 2.1Jus ad bellum 2.2Jus in bello 3Official positions 3.1World War I 4Ending a war:Jus post bellum 5Alternative theories 6List of just war theorists 7See also 8References 9Further reading 10External linksOrigins[edit]The Indian epic, theMahabharata, offers one of the first written discussions of a 'just war'. In it, one of five ruling brothers asks if the suffering caused by war can ever be justified, and then a long discussion ensues between the siblings, establishing criteria likeproportionality(chariots cannot attack cavalry, only other chariots, no attacking people in distress),just means(no poisoned or barbed arrows),just cause(no attacking out of rage), and fair treatment of captives and the wounded.[3]The war in Mahabharata is preceded by context that develops the "just cause" for the war including last minute efforts to reconcile differences to avoid war. At the beginning of the war, there is the discussion of "just conduct" appropriate to the context of war. Inancient Rome, a "just cause" for war might include the necessity of repelling an invasion, or retaliation for pillaging or a breach of treaty.[4]War was always potentiallynefas, ("wrong, forbidden") and riskedreligious pollution and divine disfavor.[5]A just war(bellum iustum)thus required a ritualizeddeclarationby thefetial priests.[6]More broadly, conventions of war and treaty-making were part of theius gentium, the "law of nations", the customary moral obligations regarded as innate and universal to human beings.[7]The quintessential explanation of just war theory in the ancient world is found inCicero'sDe Officiis, Book 1, sections 1.11.331.13.41

Christian theory of the just war begins withAugustine of Hippo[8]andThomas Aquinas.[9]Saint Augustine[edit]Augustine of Hippo, generally considered one of the greatest Christiantheologians, was one of the first to assert that a Christian could be a soldier and serve God and country honorably. He claimed that, while individuals should not resort immediately to violence, God has given the sword to government for good reason (based uponRomans 13:4). Christians as part of government should not be ashamed to protect peace and punish wickedness.[citation needed]Augustine asserted that this was a personal, philosophical stance:

"What is here required is not a bodily action, but an inward disposition. The sacred seat of virtue is the heart."[10]Nonetheless, he asserted, peacefulness in the face of a grave wrong that could only be stopped by violence would be a sin. Defense of one's self or others could be a necessity, especially when authorized by a legitimate authority:

"They who have waged war in obedience to the divine command, or in conformity with His laws, have represented in their persons the public justice or the wisdom of government, and in this capacity have put to death wicked men; such persons have by no means violated the commandment, "Thou shalt not kill."[11]While not breaking down the conditions necessary for war to be just, Augustine nonetheless originated the very phrase, itself, in his workThe City of God:

"But, say they, the wise man will wage just wars. As if he would not all the rather lament the necessity of just wars, if he remembers that he is a man; for if they were not just he would not wage them, and would therefore be delivered from all wars."[12]For the individual Christian under the rule of a government engaged in an immoral war, Augustine admonished that Christians, "by divine edict, have no choice but to subject themselves to their political masters and [should] seek to ensure that they execute their war-fighting duty as justly as possible."[13]Thomas Aquinas[edit]Nine hundred years later, Thomas Aquinas an immensely influential philosopher and theologian in the tradition ofscholasticism used the authority of Augustine's arguments as he laid out the conditions under which a war could be just:[14] First, just war must be waged by a properly instituted authority such as the state. (Proper Authority is first: represents the common good: which is peace for the sake of man's true endGod.)

Second, war must occur for a good and just purpose rather than for self-gain (for example, "in the nation's interest" is not just) or as an exercise of power. (Just Cause: for the sake of restoring some good that has been denied. i.e., lost territory, lost goods, punishment for an evil perpetrated by a government, army, or even the civilian populace.)

Third, peace must be a central motive even in the midst of violence.[15](Right Intention: an authority must fight for the just reasons it has expressly claimed for declaring war in the first place. Soldiers must also fight for this intention.)

School of Salamanca[edit]

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Growing from Aquinas arguments was theSchool of Salamanca, which expanded on Thomistic understanding ofnatural lawand just war. Given that war is one of the worst evils suffered by mankind, the adherents of the School reasoned that it ought to be resorted to only when it was necessary in order to prevent an evengreaterevil. A diplomatic agreement is preferable, even for the more powerful party, before a war is started. Examples of "just war" are:

In self-defense, as long as there is a reasonable possibility of success.

Preventive war against atyrantwho is about to attack.