Terrorism and Just War Theory
As the whole world knows, Hamas terrorists attacked Israel on October 7, 2023. The attackers achieved tactical surprise, killing approximately 1400 Israelis, mostly civilians, including children, babies, and old people. Hamas also captured more than 200 hostages and made them prisoners, presumably in underground Gaza locations.
Hamas is officially committed to the eradication of Israel. The so-called “rules of war” are meaningless to Hamas, except as those rules might be manipulated to gain tactical advantage. For example, Hamas leaders know that the Geneva Conventions forbid the direct targeting of civilian populations. They know that the government of Israel, as a member of the United Nations, is committed to following the rules of war. Therefore, Hamas has located many of its military installations near or under hospitals or mosques; they hope Israel will hesitate to attack such places because those attacks will cause civilian casualties.
To be clear: Hamas directly attacked non-combatants and, according to video evidence, tortured, raped, and murdered people who could not resist. Hamas is a terrorist organization, officially dedicated to genocide.
How should Israel respond? Specifically, what does just war theory have to say?
Just war theory divides the question of justice in war into two parts. First, jus ad bellum lays down rules for deciding to go to war: just cause, right intent, proper authority, and reasonable expectation of success. Second, jus in bello gives rules for just warfighting: no torture or killing of captives, distinguishing combatants from non-combatants, and proportionality (harms to non-combatants must not be disproportionate to military gains).
Israel’s prime minister has claimed that Hamas’ terrorist attack gives Israel a just cause; therefore, Israel’s war with Hamas is just. Such reasoning is too simplistic. It seems to me Israel certainly has a just cause, its government is a proper authority, and Israel’s great military capacity gives it reasonable expectation of victory. If Israel also has a right intent, Israel’s war against Hamas would comply with the rules governing the decision to go to war (jus ad bellum).
What is Israel’s goal in the war against Hamas? The prime minister made this clear: the elimination of Hamas as a terrorist and governing organization.
I should note here that Hamas has governed Gaza—more than two million people—since 2006. Since Hamas came to power in Gaza, they have not allowed elections. Like many governments in history and today, the legitimacy of Hamas as a government is open to question. Nevertheless, Hamas is both a government and a terrorist organization, a fact which complicates Israel’s war aims.
Eliminating a terrorist organization seems to be a right intent. Eliminating the government of a neighboring state is much more questionable. Significantly, Israel’s prime minister has said little about what government should replace Hamas in Gaza. The prime minister has said that Israel does not intend to govern Gaza directly. But for Israel to succeed in its stated aim—eliminating Hamas as a governing organization—Israel will have to conquer Gaza. Its military forces will have to occupy Gaza (or large parts of it) for some period of time, however brief. As regards right intent, Israel’s leaders need to face into the question of government for Gaza. It cannot be a right intent to invade a neighboring country only to leave it in the kind of chaos and lawlessness we see in Haiti.
What about jus in bello? I have read no reports of Israel torturing or killing captives, so I will assume Israel’s war will pass that test. Discrimination? Israel’s government says its war is aimed at Hamas, not the people of Gaza, so it clearly recognizes the problem. The civilians of Gaza do not deserve to be killed or displaced merely because they have the misfortune of being governed by a terrorist organization.
The modern proportionality rule descends from a more straight-forward medieval rule in just war theory: no attacks on non-combatants. After all, the fundamental idea of just war theory is to oppose and stop evildoers, not commit more unjust acts; attacks directed at non-combatants are inherently unjust. But the practice of war, even in medieval times, forced just war theorists to modify the rule. Killing non-combatants—that is, planning and carrying out military attacks that will kill innocent people—may be justifiable if such killing is necessary to accomplish a legitimate miliary objective. We’re not talking about “accidental” deaths here; according to the proportionality rule, deliberate attacks that kill innocents are “just” if those attacks are aimed at legitimate targets. Proportionality only says that such non-combatant deaths must not be “disproportionate” to military gains.
Israel’s war against Hamas is now in its 28th day. The prime minister has repeatedly warned his people (and the world) that the war will be long and hard. Instead of an immediate and massive counterattack, Israeli missiles and bombs hit targets in Gaza for three weeks. In recent days Israeli ground forces have begun incursions into Gaza.
Gazan officials report that more than 9000 people have died in Gaza. Such numbers cannot be verified. Hamas controls information from Gaza, and it is in their interest to paint Israel’s war as evil. Nevertheless, it is safe to assume that civilian deaths in Gaza number in the thousands, a factor of four or five times the death toll of Hamas’ attack on October 7.
How many Hamas fighters are in Gaza? No one knows. How many must Israel kill in order to achieve its goal: the elimination of Hamas as an organization? No one knows, though we may assume that Israel’s military officials have established benchmarks they will use to evaluate their war. These benchmarks probably include Hamas’s ability to fire missiles at Israel, estimates of how many fighters Hamas has, names of important Hamas leaders, and other things. In each case, Israel will aim to reduce Hamas’s capabilities and manpower to a negligible level.
According to the prime minister, Israel’s war is in its early stages. By all accounts, Hamas has hidden its forces underground in Gazan cities. To eliminate Hamas as a terrorist and governing organization, Israel must be prepared to fight in cities: building to building, tunnel by tunnel, block by block.
Israel has tried to reduce civilian casualties by urging Gazans to flee to the south. Tens of thousands have done so, but many more remain in northern Gaza. To be sure, southern Gaza is not safe; Israeli airstrikes hit targets there. Further, we may assume that if the war is long, and if most Gazans move south, Hamas will move some of their forces south to benefit from human shields. In that case, Israel will face the “military necessity” of bombing areas of Gaza to which Israel urged civilians to flee.
The government of Israel needs to face hard realities. To achieve its stated goals, Israel will have to kill many more non-combatants than have already died. I am no expert, but it’s possible that 100,000 or more civilians would die before Israel can eliminate Hamas as a functioning organization. How can such slaughter of innocents pass the proportionality test?
Conceptually, the proportionality test is deeply flawed. The prime minister of Israel may well say (after the fact) that the elimination of Hamas as a terrorist and governing organization was so important that the death of any number of civilians was justified. At the same time, Israel will dispute casualty figures offered by various antisemitic voices claim; the actual death toll, Israel will say, is less than whatever number its enemies announce. Such debates only matter if there is some hard content to “proportionality.” How many innocents must die to render Israel’s war “disproportionate”? Suppose, as imaginative test, half the population of Gaza (1.1 million people) died before Hamas was eliminated; would that be “disproportionate”?
I predict that Israel’s leaders will claim, after the fact, that their war against Hamas obeyed the rule of proportionality. They will make this claim no matter how many innocent Gazans die. At the same time, critics of Israel will claim Israel’s war violated the proportionality test—again, no matter how many civilians die.
I urge this conclusion: the “proportionality” rule is conceptually flawed. It places no real limit on the violence of war.
My own view is that just war theory is a 1600-year-old mistake. Followers of Jesus should reject it. Of course, that will mean nothing to the leaders of Israel, who make no pretense of following Jesus. Sadly, the vast majority of Christians today (and in the past) give only lip-service to their Lord, who commanded us to love our neighbors, including our enemies.
Some philosophers, pointing to weaknesses like the conceptual impotence of the proportionality rule, openly reject just war theory. Some “realists” say that states fight for their own purposes and define success on their own terms. Moral norms do not apply. The so-called “laws of war” are really just the (self)justifications of nations that win, after the fact. Other “realists” might agree with all that, but then plead that humanity needs some way to apply morality to war, lest we kill everyone.
