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Conventional Just War Theory is Profoundly Unjust

2018/2/12 — 17:57

第二次世界大戰資料圖片 l National Museum of Health and Medicine @flickr

第二次世界大戰資料圖片 l National Museum of Health and Medicine @flickr

Conventional just war theory is composed of jus ad bellum, jus in bello and jus post bellum, which is supposed to provide moral guidance of waging war, of military operations in the battlefield and of ending war respectively. However, this article argues that many of its principles are either flawed or vague.

It is well-known that jus ad bellum justifies the declaration of war in only extreme exceptional circumstances by limiting it to have just cause, right intention, reasonable chance of success, proportionality of ends and as the last resort of a legitimate authority. Yet some of the principles of jus ad bellum are either excessive lenient or excessive restrictive.

First, the definition of “extreme exceptional circumstances” is vague and the arguments developed on this basis are potentially “slippery slope” (Primoratz, 2013, p. 102). In other words, a proper authority might exaggerate the imminence and seriousness of the threat it faced (Nathanson, 2006, p. 22), either deliberately or unconsciously. Then the principle of last resort would be misapplied. Second, it is sometimes not clear that a legitimate state has just enough cause(s) to wage war against others, especially when it does not face any direct military aggression from other states but suffers from grave and systematic injustice in the international arena. For instance, if some developing countries were seriously exploited by some developed countries economically, it would still be controversial for the former to justify waging war against the latter. Third, it is doubtful that a de facto sovereignty state, which has inadequate or even no moral legitimacy, can wage a morally justified self-defence war, especially if the demise of it would more likely lead to better protection of human rights of its civilians.


Fourth, and more importantly, jus ad bellum pays inadequate attentions to the importance of financial consideration of waging war, albeit it is a common sense that war is often extravagant (Oberman, 2017). The financial consideration of waging war can be divided into two types.

First, some may argue that it is morally condemnable to wage war to against other states if it were unaffordable to a legitimate state. This kind of consideration might be incorporated into the thick notion of reasonable chance of success, because without healthy financial condition, it seems highly implausible for a legitimate state to win a war in order to save the innocent citizens of the enemy state, and the interests of its citizens would most likely be sacrificed simultaneously. Yet this line of thought is biased in favour of rich states and is sometimes counterfactual. If a poor state should never engage into war, then China and some other Asian states’ self-defence war against Japan’s aggression during the WWII would be unjustified. But the evidences clearly suggest that the defensive states are the victorious side, which rebuts the assertion that a state must be defeated in a war because of having financial difficulties. Furthermore, the absolute rejection of waging self-defence war disdains any justification of protecting its citizens, deterrence and upholding political independence, and at its extreme, this appeasement policy would encourage the revival of Nazism, Fascism and militarism indirectly.


The deontological justification of war, nevertheless, is conditional. A legitimate state cannot always justify its self-defence war, even if its territory was invaded by another state. There are probably some other means which is more cost-effective than war to regain the lost territory, such as diplomatic negotiation. And if the territory lost was not fatal to the survival of a legitimate state, it would be preposterous to prioritise waging self-defence war over appealing to peaceful means so as to avoid any unnecessary harm or even death. It explains why the CCP’s military takeover of Hong Kong during the period of British colonial rule, if it happened, would violate the principle of proportionality and of the last resort. Likewise, it would be morally repugnant for the CCP to provoke military confrontation in South China Sea under the name of preserving absolute state sovereignty (Chang 2018), since the sovereignty of South China Sea is both controversial and not proven pivotal to the survival of China.

The second type of financial consideration is cost-benefit analysis among two conflicting options: fulfilling the moral duty of poverty alleviation versus waging war to save lives. Echoing Kieran Oberman’s (2017) view, waging war to save lives is a morally wrongdoing if the costs involved could be better use to fulfil the moral duty of alleviating poverty, which is arguably more effective to protect the right to life in many circumstances. The conventional interpretation of the principle of proportionality, unfortunately, fails to realise the necessity of including the costs of violating the duty of poverty alleviation due to war into calculation (Ibid, p. 4).

This line of argument does not imply that a legitimate state have any moral duty to assist the poorest people to live luxuriously, because heavy taxation would be necessary to back up this ambitious project, yet a legitimate state should only have the political powers to demand its citizens to make moderate level of altruistic sacrifice (Ibid., pp. 10-11). And it does not “rule out the possibility that war could prove proportionate even if it saves fewer lives than it costs. Saving lives is not the only thing that matters. There could be other benefits of war that warrant inclusion within a proportionately calculation (e.g. defending territory or deterring aggression)” (Ibid, 8). It helps to explain why China and some other Asian states’ self-defence war against Japan’s aggression during the WWII, as stated before, could still be justified according to the new interpretation of the principle of proportionality. Yet it also follows that it would be appropriate for a legitimate state to wage a war only if it did not hinder moderate level of poverty alleviation directly or “if the benefits were so great as to outweigh the costs, including the costs of unalleviated poverty” (Ibid., pp. 5-6). The new interpretation is also arguably resorted to both distributive justice and “value pluralism” rather than “utility maximisation” (Ibid, pp. 17-18).

Furthermore, the justification of waging self-defence war directly should be relatively lenient than the justification of humanitarian intervention or providing assistance to others states for waging self-defence war, ceteris paribus. The motive for waging war can sometimes be as altruistic as poverty alleviation, but given that a legitimate state should care about domestic interests primarily, it should prioritise using tax to alleviate poverty over waging altruistic war (Ibid., pp. 10-12). This claim is particularly right if the money spent on altruistic wars could be used to provide better protection of the right to life domestically (Ibid, p. 7). Therefore, it was morally wrong for the Iranian government to send troops to help the neighbouring Shiite states or to fund them to counteract with the Sunni influence or to fight against Islamic State (Nuruzzaman, 2016) at the expense of the livelihoods of the domestic grassroots (Pillar, 2018). By the same token, it would be a big mistake for the US government to wage nuclear war against North Korea (Bandow, 2017; Chang, 2017) because it is extremely expensive and ineffective to save lives.

It is further argued that the conventional just war theory imposes excessive heavy moral burdens not only to taxpayers but also to the frontline soldiers. For instance, while the three principles of jus in bello demonstrates the significant characteristic and rationale differences between just war and terrorist attack, they strictly require the frontline soldiers to have sufficient knowledge, information and degree of rationality to make the correct judgement in the ex-ante sense (Primoratz 2013, p. 99). However, this article would not jump to the conclusion that such demanding requirement would never be met, and the permission for killing should remain restrictive in principle at least. Rather, the crux of the problem is that just war theory never put the human rights of frontline soldiers into serious consideration. They are required to “work” under the condition of extremely heavy pressure, facing high risks of being wounded, losing life and witnessing their comrades in arms losing their life, but jus post bellum never mention about how to compensate them or to provide assistance for them to rehabilitate physically or/and mental rehabilitation, despite the emphasis of rehabilitation in the macro level. As a consequence, they suffer undeservedly. David Finkel’s (2013) famous non-fictional book “Thank You for Your Service” reveals that the percentages for retired American frontline soldiers to suffer from post-traumatic stress disorder after returning home are non-negligible.

Because of ignoring the opportunity costs of alleviating poverty due to war and abhorring human rights of frontline soldiers, a legitimate state could still wage a seriously unjust war even if it completely fulfilled the criteria of conventional just war theory.



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