Jus ad bellum

One school of thought about the morality of war holds that it is impermissible to fight in a war that lacks a just cause and that soldiers who fight in such a war cannot evade responsibility for their participation by claiming that the government alone is responsible for determining whether the wars it fights are just. It is, however, commonly argued against this view that it is unreasonable to expect soldiers to be competent to judge whether a war is just or unjust. They typically have limited factual information, believe that theirs is a just society incapable of unjust aggression, trust the claims of their government and superior officers, and so on. Soldiers who fight in wars that are objectively unjust because they lack a just cause (“unjust combatants”) therefore tend to have one or the other of two mistaken moral beliefs: either that their war is just or that, although their war may be unjust, their participation in it is nevertheless morally permissible. When this is so, does that mean that these soldiers are morally justified in fighting? If not, does it mean that they are at least morally excused – that is, that even though they act wrongly, they are not blameworthy for doing so? Suppose that certain unjust combatants fight without knowing that their war is unjust. Their ignorance may take several forms. They may be mistaken about matters of empirical fact that are relevant to the moral evaluation of the war. The moral conclusion they draw from the mistaken empirical beliefs might or might not be the correct conclusion to draw from those beliefs. Either way, given that the factual beliefs are false, the probability that the moral belief based on them is true is bound to be low. Alternatively, their belief that their war is just may be false even though all their nonmoral beliefs that are relevant to the moral evaluation of the war are true. That is, although they know all the relevant nonmoral facts, they draw the wrong moral conclusion. In general, mistakes of this sort – those that are purely moral – are significantly less exculpating than mistakes of nonmoral fact, assuming that in both cases the degree of the person’s diligence, or lack of diligence, in the formation of the beliefs is the same. If someone knows all the nonmoral facts relevant to the evaluation of a war and there are no special circumstances that might excuse him for drawing the wrong moral conclusion, we regard him as culpable if he fails to draw the right conclusion. If, for example, a Nazi soldier knows that Poland poses no threat to Germany but believes that it is morally justified to seize Polish land by force for the expansion of the superior German nation, he has little or no excuse for his participation in aggression against Poland. Because such purely moral mistakes seldom

constitute a significant excusing condition, the following discussion of erroneous beliefs in war will concentrate on mistakes of nonmoral fact. It is a commonplace in epistemology that it can sometimes be reasonable for a person to have a belief that is in fact false – that is, that he or she may be epistemically justified in having a belief that is false. This may be true when the relevant evidence available to the person is systematically misleading. If an unjust combatant has beliefs about nonmoral facts that are false but epistemically justified and he draws the moral conclusion that would be appropriate if those beliefs were true, we can say either that what he does on the basis of that conclusion is subjectively right or justified, or that it is objectively wrong but nevertheless excused, either fully or at least to some degree. I will assume that our concern here is with objective justification, so that action that is objectively unjustified is at best excused. One reason that action based on epistemically justified nonmoral beliefs might be less than fully excused is that there are degrees of epistemic justification. A person may be justified in having a certain belief, but only barely so. What this means is that while he is justified rather than unjustified in having the belief, the degree to which he can be justifiably confident in the truth of the belief is low. Alternatively, one might say that the degree of credence that the belief warrants is low. There are thus various possibilities in the case of the unjust combatant whose relevant nonmoral beliefs are epistemically justified: they may be weakly justified, strongly justified, or justified to some intermediate degree. These possibilities are relevant to the question whether he is morally excused for fighting. For whether and to what extent he has an epistemically-based excuse for fighting depends on whether and to what extent the nonmoral beliefs that underlie his belief that he is acting permissibly are epistemically justified. Suppose, for example, that his relevant nonmoral beliefs are epistemically unjustified but that he accepts them uncritically because they cohere well with the distorted conception of the world supplied by an ideology he accepts. In that case, he has little or no epistemically-based excuse for participating in his side’s unjust war. Suppose, next, that the false nonmoral beliefs that support his decision to fight are epistemically justified, though only barely. That his beliefs are justified is certainly an excusing condition. Yet given that these beliefs warrant only a low level credence, the excuse is weaker than it would be if they instead warranted a high degree of credence – that is, if he could justifiably have a high degree of confidence that his relevant nonmoral beliefs are true. There is another factor here that is perhaps even more important than the degree of credence he is warranted in according to his beliefs. This is that the degree to which his justified beliefs excuse his objectively wrongful action depends on how much is at stake, morally, in the choice he must make between fighting and not fighting. Suppose that, if he did not have the false nonmoral beliefs that support the permissibility of fighting, he would refuse to fight. The more that is at stake morally in the decision he makes based on these beliefs, the more important it is that his beliefs be true; and the more important it is that the beliefs be true, the less excuse he has if he is in error and acts on the basis of false beliefs. More specifically, the more that is at stake morally in the choice an agent makes on the basis of some belief, the higher the level of justified confidence the agent must have in the truth of the belief in order for the belief to ground an excuse of a fixed degree of strength, if the belief is in fact false. It may help to clarify that last claim to give a schematic example. Suppose a soldier is commanded to fight in an unjust war. He believes, however, and with a moderately high level of credence, that the war is just and that his participation in it is permissible. Suppose that he is in fact epistemically justified in having that belief and in according it that degree of credence. Next imagine two possible variants of the example. In one, the war is small, victory by his side would not be tragic, and in any case he will be deployed in an area in which there is very unlikely

to be any fighting, so that his participation is unlikely to make any significant difference. In these conditions, his belief may provide a strong excuse for his participation. In the other possible variant, victory by his side would be a catastrophe from an impartial point of view and his participation would be likely not only to involve the killing of numerous enemy combatants but also to make a significant contribution to his side’s war effort. In these conditions, his belief, although justified, would provide only a much weaker excuse for his participation. This is intuitively plausible. The same false belief, with the same degree of epistemic justification, provides a stronger excuse when what is at stake is of lesser moral significance. When what is at stake is of greater moral significance, his belief must be better grounded to provide an excuse of equal strength if the belief turns out to be false. “What is at stake morally” is not just a matter of the moral gravity of what a person will do if he acts on the basis of an epistemically justified belief – for example, the moral gravity of killing innocent people, which is what a combatant will do if he fights in a war that he justifiably but falsely believes is just. What is at stake is instead comparative: it is the difference between what may happen if an agent acts one way and what may happen if he acts in another way. In the case of a soldier, what is at stake in whether or not he fights is the moral difference between the probable outcomes of both options. In this context, the notion of “what is at stake morally” presupposes uncertainty. Thus there are possible moral costs either way. When a soldier is deliberating about whether to fight in a war, and trying to determine whether participation is permissible, what is at stake morally is the moral difference between the two ways in which he might get it wrong: by fighting in a war that is unjust and by refusing to fight in a war that is just. What makes the soldier’s predicament so difficult morally is that, in a choice between going to war and not going to war, there is usually a very great deal at stake, and the conditions in which he must choose are typically conditions of substantial factual and moral uncertainty, in which the justified level of credence in any set of relevant factual beliefs is quite low. What should soldiers do in these circumstances? Should they, for example, act on the basis of the factual and moral beliefs that have the highest justified level of credence? Here are a few simple observations that seem plausible, and that are specifically focused on the case of unjust combatants. Suppose a soldier who voluntarily enlisted earlier is suddenly commanded to fight in a war that has begun unexpectedly. He has little leisure for reflection and the relevant facts are obscure. His government has asserted various factual claims that, if true, would support its further claim that the war is just. But these factual claims have been disputed or denied by others, including experts among the soldier’s own fellow citizens. The level of credence he is justified in having in either of the opposing sets of factual claims is low. It is clear, however, that his own country is not in danger. The war is thousands of miles away in a remote country that he knows almost nothing about. He does know, however, that most of the people he would be fighting against are citizens of the country in which the war is being fought. What ought he to do? He might reflect on his options in the following way. The war is either just or unjust, but he does not know which. Indeed, the one thing he does know is that he lacks relevant knowledge, both factual and moral. Suppose that as a morally scrupulous person, his primary concern is with the impact of his action on the people in the country in which the war is occurring: that is, the people he would be fighting for and those he would be fighting against. If, on the one hand, he refuses to fight and the war is just, he will fail in his duty as a soldier to protect innocent people. He may even allow innocent people to be killed whom he could have saved. Yet if he refuses to fight, he is likely to be replaced by someone else who will be as effective as he would have been. Perhaps the real victim of his refusal to fight would be the person who would replace him and be exposed to the risks of war in his stead.