Photograph: Dexter

Many commentators have condemned the high civilian death toll in Operation Protective Edge, arguing that the IDF's use of force has been disproportionate—the negative effect of military action is too great to be justified by the good it achieves. Israel alleges that Hamas and its allies are using civilians as human shields, by storing military supplies close to civilian dwellings, building tunnels beneath mosques and homes, and firing at Israel from positions close to civilian buildings.[1]

Based on this claim, two moral arguments are made: first, that because Hamas uses civilians as human shields, Hamas is responsible for their deaths, not the IDF. In other words, those civilians do not count among the negative effects of the IDF that must be outweighed by the positive to satisfy proportionality. Second, insofar as Hamas is intentionally trying to use the IDF's concern for civilians as a means to advance its own military objectives, one of the positive achievements of Protective Edge is that the IDF is resisting Hamas’ attempt to subvert morality in the pursuit of an unjust cause. Analogously, we ought not make deals with kidnappers because doing so encourages more and more severe repetition of the same technique, even if, were we to consider this case in isolation, it would clearly be appropriate to make a deal.

Whether or not Hamas is in fact using civilians in this way, these moral arguments are problematic. Let’s take them in turn.

The first argument rests on the spurious assumption that responsibility is zero-sum. Hamas being fully responsible for the civilian deaths does not preclude Israel also being fully responsible. This point is so familiar from criminal law—otherwise we could not try more than one person for the same murder—that it is surprising that it needs to be repeated.

If Hamas uses civilian shields, is the IDF responsible for their deaths?

Still, one might think that Hamas' joint responsibility provides some grounds for discounting the weight of those innocent civilians' lives when tallying up the bad effects of the IDF's actions. Suppose that Hamas were to literally treat innocent civilians as hostages by advertising an intention to kill a certain number of them should the IDF not withdraw. Then many would think it plausible that those deaths should not receive the same weight in the proportionality calculation as those directly inflicted by the IDF, in part because of the 'intervening agency' of Hamas. Perhaps human shields are analogous to hostages in this way.

We should resist this conclusion. Innocent people's lives have weight in the proportionality calculation because of their moral status—their right to life. This status, and these protections, cannot be diminished by the impermissible actions of some third party. And even if you reject that fundamental commitment, hostages are not analogous to human shields: it surely makes a difference to the argument whether the enemy's involvement is genuinely intervening. If side A threatens harm to hostages unless side B withdraws, then the harm to those hostages is not solely caused by side B's actions, but is the product of a subsequent voluntary choice by A. But if side A uses innocent civilians as human shields, then side B's decision to use force that will harm those civilians is necessary and sufficient for them to be harmed. This must make a difference. Finally, even if you think these two cases are analogous, any side that claims to have a just cause to fight in war must believe that their opponents are partly responsible for all the civilian deaths that subsequently occur. Had they not given the just side cause to fight, then none of those deaths would have happened. So all the resulting civilian deaths should have the same weight in the proportionality calculation, whether they were human shields or not. If Israel believes their cause in Gaza is just, they cannot consistently treat human shields differently from any other civilian victims.

What of the second argument, that resisting Hamas deters the use of human shields (and similar methods) in the future? It is hard to be sure: who knows what the long-run consequences of this operation will be? But speculation of this kind would miss the point. The argument claims that the IDF must kill these innocent civilians, because capitulation at this point would result in future belligerents using the same tactics as Hamas, to the detriment of international law and the protection of civilians more generally. That is, killing these civilians is a means to deter the use of human shields in the future. The proportionality constraint licenses only unintended harms to the innocent that are inflicted as a foreseeable side effect of achieving some justified objective. Some think that the distinction between intended and merely foreseen harms is mere moral window-dressing, but most would agree that harming civilians as a means is harder to justify than harming them as a side effect. People have status, we are ends in ourselves; we are not tools or resources to be used for advancing others' goals. The constraint on harming people as a means is especially stringent. The innocent civilians who have been used as human shields by Hamas must not be used again by the IDF as a means to deter the use of such tactics in the future.

Moral arguments are unlikely to affect the methods and motivations of either side in this conflict. But insofar as they are used, we should get them right. Even if Hamas is using innocent civilians as human shields, that has no bearing on whether operation Protective Edge has been proportionate.

[1]This claim is also a central component of the IDF's public justification for Protective Edge. F.M. Kamm focuses on whether the killing of human shields can properly be described as unintentional. I am granting that it can.