War is always evil, but some thinkers have maintained that under limited circumstances it may be the lesser evil. From Cicero to St Augustine, Thomas Aquinas to Hugo Grotius, philosophers and theologians have proposed numerous criteria for determining if a war is just. According to contemporary Just War Theory, a war is just only if it meets the six conditions presented in the following debate. The theory is underwritten by the dual assumptions that the moral reality of war is not fixed by the actual activities of soldiers but by the opinions of mankind and that the truth is we want, even in war, to act or to seem to act morally. It has been formulated to prevent war, not justify it; a nation must satisfy all six conditions or the war is not just. The theory is designed to show states the rigorous criteria they must meet to justify the use of violence and prompt them to find other ways of resolving conflicts.
Wars are just if the cause is just. Nations should be allowed to defend themselves from aggression, just as individuals are permitted to defend themselves against violence. In the UN Charter, signed in the wake of World War II, article 2, paragraph 4 altogether prohibits the use or threat of force with only self-defence, as stated in article 51, permitted as a justification to the resort to arms.
 United Nations. (1945, June 26). Chapter I: Purposes and Principles. Retrieved May 9, 2011, from Charter of the United Nations: http://www.un.org/en/documents/charter/intro.shtml
Just cause is an elastic concept. Who determines what is “aggression”? Could violating a disputed border region (e.g. Ethopia-Eritrea, Pakistan-India) or imposing economic sanctions (e.g on North Korea) be aggression? And if a state is unable to defend itself, can another state intervene militarily on its behalf? These borderline cases make invoking this criterion very problematic.
The intentions behind the war must be good. States have the right to use war to restore a just peace, to help the innocent, or to right a wrong. For example, the US and NATO were justified in using force in Bosnia and Kosovo. Waging war was far more ethical than standing by and permitting genocide and “ethnic cleansing”.
Reality is a lot murkier than theory. How are we to determine a state’s intent? Sometimes good intentions are bound up with bad; public justifications for war may not always represent the real reasons. And who is determine if a peace is just or a wrong has been committed? The nation initiating the war will use its own values to justify its intentions, and these values may be at odds with those of the other party to the conflict. Furthermore, it is altogether possible to fight a war for selfish motives and nevertheless protect civilians and reduce suffering in so doing.
The war must be lawfully declared by a lawful authority. This prevents inappropriate, terrorist-style chaos, and ensures that other rules of war will be observed. For example, when states declare war, they generally follow specific legislative procedures; a guaranteed respect for such procedures is likely to ensure that the nation will respect international humanitarian law, formally codified in the Geneva Conventions of 1949 and updated in the Additional Protocols of 1977.
Many nations wage war without official declaration (e.g. the USA’s involvement in Vietnam) and act unilaterally instead. Such unilateralism does not necessarily lead to an inevitable circumvention of the Geneva Conventions, it merely avoids the bureaucracy necessary to draw authoritative approval. Moreover, who is to decide which entities can and cannot issue calls to arms? Legitimate authorities have sanctioned some of the most horrific wars in history.
War must be a last resort. The state is justified in using armed force only after it has tried all non-violent alternatives. Sometimes peaceful measures – diplomacy, economic sanctions, international pressure, or condemnation from other nations – simply do not work, but they must at least be tried in order to give every chance for a peaceful resolution to a crisis.
Sometimes going to war before all alternatives are exhausted is the most moral action. For example, a nation might decide to go to war if it determines that waiting would enable to the enemy to increase its strength and to do much more damage than an early war would have inflicted. This, after all, is the bitter lesson of the failure of appeasement in the 1930s. Waiting might allow an invading state to entrench itself so that far greater force would be necessary to remove it at a later date.
The goal of the war should be proportional to the offense, and the benefits proportional to the costs. For example, when an attacker violates a nation’s border, a proportionate response might extend to restoring the border, not sacking the attackers’ capital. A war must prevent more suffering than it causes.
The Coalition that formed under the aegis of the United Nations to repel the Iraqi invasion of Kuwait fought a proportional conflict to the extent that they did not march on Baghdad after they had pushed the Iraqi Army out of the occupied territory.
We have seen that a proportional response frequently doesn’t work. Suicide bombers continue to blow up victims in the Middle East despite the response. Why should a nation tolerate continued aggression for the sake of proportionality? And if a nation knows it is likely to be attacked, why should it wait to disarm the aggressor? Is not pre-emptive action justified to prevent the loss of innocent life? Finally, what of deterrence: a vigorous response to an aggressive act may not be strictly proportionate, but by making all potential aggressors think twice about future actions, it can be justified as saving more suffering in the long run.
The war must have a reasonable chance of success. War always involves a loss of life, but expending life with no possibility of achieving a goal is unacceptable. Thus, if a fighting force cannot achieve its goal, however just, it should not proceed. Charging an enemy’s cannons on horseback or throwing troops at a pointless occupation are clearly not just actions.
Sometimes it is morally imperative to fight against overwhelming odds, as resistance fighters did in World War II. Also this condition may give large nations free rein to bully small ones because they could not win a war. It also may cause a country to surrender in a war it might actually win. Weak countries have won wars against powerful ones – look at the American Revolution. Finally, the point at which a war became unwinnable, and therefore unjust by this definition, is often only identifiable with hindsight – consider the Soviet occupation of Afghanistan, or the American involvement in Vietnam.
The formulation of the just war doctrine, a moral framework for the institution of war, inadvertently serves to legitimise its activities and inherent barbarity. It undermines the intuitive norm against warfare by emphasizing the ‘just’ and undercutting the ‘war’, leading to a framing of public discourse whereby anti-war campaigners can be presented and ostracized as traitors and soldiers, even of aggressor nations, heroes.
In many religions war can never be legitimised for example in Buddhism “War happens. Buddhism does not deny such facts. It tries to understand how war happens. But Buddhism never accepts or legitimizes war as necessary or “just.” One naturally defends oneself when attacked. One may prevent someone from doing harm to others. Neither, however, justify harming the alleged or imagined perpetrator/aggressor.”
 Bhikkhu, S. (2003, March). "Just War" is an oxymoron. Retrieved May 9, 2011, from Liberation Park: http://www.liberationpark.org/bpf/just-war-oxy.htm
War is a necessary element in international affairs when there is no scope for diplomacy and conditions dictate that force is necessary to prevent or stop suffering. Few would argue that the United States was acting unjustly in entering the 2nd World War, or that more generally the defeat of the Nazis was an unjust act on the behalf of the Allies.
Furthermore, just war theory has little to say on the overall existence of war, but merely seeks to regulate war as a permanent feature of international society. War, as an institution and a human activity, has existed for as long as there have been political communities. The resort to force is therefore not one made due merely to a belief in its legitimacy but a belief in its utility. Just war theory acts therefore as a series of moral criteria to regulate the resort to warfare in order to prevent, rather than exacerbate, war for war’s sake. It recognizes the ‘war is hell’ mentality and is, if anything, born from it, encouraging a resort to force only in cases where diplomacy is unable to function and war is strictly necessary. Even then, jus in bello principles apply to regulate the conflict itself, ensuring that a just war does not descend into the use of illegitimate means and methods of warfare. It does not purport to comment on the matter of the existence of warfare, merely recognises its occurrence and seeks to regulate both its regularity and bloodshed.
The just war doctrine establishes a framework for leaders to justify the resort to force in any given situation whereby they can find ostensible evidence for all the necessary criteria. It, in other words, leaves war on the table constantly as an option; diplomatic negotiations and bargaining must succeed with the constant shadow of war looming as not only a realistic eventuality, but an eventuality that could potentially be deemed ‘just’ by either side. Any such doctrine therefore renders the resort to war as far too permissive, and encourages the false presumptions of aggressive states that their motives are not only self-serving but legitimate.
War has always been an option in international affairs; few rulers before just war theory was developed felt constrained by the absence of such a moral framework. What the just war criterion provide for is a regulatory framework whereby war cannot break out before at least one side satisfies the criterion. As such, this ensures a temporal space for diplomatic negotiations to play out and if necessary, for either top-down pressure from more powerful states or bottom-up pressure from the public to alleviate any desire for war.
The ‘Global War on Terror’, according to the Bush administration and its legal team, ushered in a new ‘paradigm’ of warfare. Characterised by non-state actors, acting across international borders, often from failed states, just war theory is arguably out of its depth in dealing with it. The United States’ war in Afghanistan was not proportional, had little prospect of success in eradicating the ideology of Al-Qaeda itself and certainly was not a last resort, but nevertheless many felt it was ‘just’ in 2001.
 Lukach, T. (2005, March 17). War on Terror creates New Paradigm for Guard, Reserve. Retrieved May 9, 2011, from U.S. Department of Defense: http://www.defense.gov/news/newsarticle.aspx?id=31175
The traditional just war framework may be difficult to apply to the contemporary war on terror, but whilst war remains, we must possess the just war framework as a strategic tool to both prevent and regulate its occurrence. Whilst they may involve the alteration of certain criteria, as has happened throughout its history, it does not suggest it has lost all use. The Bush administration’s attempts to circumvent the jus in bello principles of non-combatant immunity were stalled, albeit belatedly, by widespread public disapproval, proving the basis for just war thinking is not in vain idealism but moral intuition. Therefore the just war doctrine is not only necessary but to an extent, innate.
Bhikkhu, S. (2003, March). "Just War" is an oxymoron. Retrieved May 9, 2011, from Liberation Park: http://www.liberationpark.org/bpf/just-war-oxy.htm
Lukach, T. (2005, March 17). War on Terror creates New Paradigm for Guard, Reserve. Retrieved May 9, 2011, from U.S. Department of Defense: http://www.defense.gov/news/newsarticle.aspx?id=31175
United Nations. (1945, June 26). Chapter I: Purposes and Principles. Retrieved May 9, 2011, from Charter of the United Nations: http://www.un.org/en/documents/charter/intro.shtml