The Iran War Is Not a Just War
Operation Epic Fury fails almost all the tests of righteous warfare.
FOR ALL THE IMPASSIONED IMPROMPTU defenses of the current war in Iran, there have been remarkably few that have used the traditional criteria Western (and many non-Western) theologians, ethicist, politicians, and soldiers have used to evaluate the righteousness of armed struggle, the “just war” principles. Even those leaders who have called the war “just” have not engaged with any of the specifics of just war reasoning. The paucity of such efforts likely results from the fact that this war cannot be considered a just war when all the relevant criteria are considered.
Just war criteria concern the conditions under which it is morally acceptable to enter into war (jus ad bellum) and the manner in which war must be conducted (jus in bello). Jus ad bellum and jus in bello principles are embedded within the law of armed conflict and international humanitarian law, including in the United Nations Charter (particularly Articles 2(4) and 51) and the Geneva Conventions. Although these principles are fundamental to modern LOAC and IHL, they are essentially ethical considerations, dating back to ancient sources, which were developed in the Western intellectual tradition by thinkers such as Augustine, Aquinas, and Grotius. In the context of the Christian tradition developed by Augustine and Aquinas, just war reasoning modifies, but does not displace, a fundamental orientation towards peace—that is, towards pacifism.
The jus ad bellum criteria include just cause, last resort, proper authority, right intention, reasonable chance of success, and an end proportional to the means used. Most of the public discussion about the morality of the Iran war has focused solely on just cause.
The fundamental axiom of the “just cause” criterion is that war must be defensive, not aggressive. Defenders of the war rightly highlight the threats posed by the Iranian regime, and these threats could provide a strong basis for just cause. They argue that the United States and Israel were justified in striking Iran because of the threats Iran poses to both countries, both indirectly through proxy action such as supporting Hamas and Hezbollah, and directly, including through potential nuclear weapons. There is no doubt that Iran is hostile to Israel and the United States, and the October 7th attacks almost certainly could not have happened without Iran’s support. If the United States or Israel possessed intelligence showing that Iran was actively plotting to support another October 7th–type attack through its proxies, that it was about to deploy a dirty bomb, or that it was near completion and use of a nuclear weapon, there would be just cause for a preemptive strike.
But neither the United States nor Israel have released any information publicly demonstrating anything of this sort. A preemptive strike requires some clarity about the immanence of the threat. It’s not enough that an adversary state is enhancing its military capabilities, which is part of every state’s inherent right of self-defense. Nor is it enough that there have been diplomatic tensions or even a history of conflict—if that were enough, a perpetual state of war would be justified almost everywhere in the world.
The defense of others can supply just cause for war, and some just war theorists have argued that this could include intervention by other states when a tyrannical regime is killing its own citizens. Iran recently massacred thousands of its own citizens in response to recent protests, so it provides a strong case for this kind of argument. An interventionist case for just cause, however, is not the ordinary case, or else states would be free to meddle in each other’s affairs on the grounds that some policy or another is hurting people. The just cause criterion for the present Iran war, then, seems at least to be in serious doubt absent publication of more evidence of immanence, except perhaps in the possibly extraordinary defense of Iran’s civilian population against the brutality of the existing regime. If just cause were the only element of a just war analysis, this would leave us feeling perhaps a bit morally concerned, but not outraged. Iran has acted aggressively in the past, it will likely act aggressively again if it remains free to act as it wishes, and the regime has slaughtered its own innocent citizens and will do that again as well. Maybe just cause isn’t quite there right at this moment, but it’s close enough. Indeed, some commentators have suggested that the immanence criterion for jus ad bellum in international law should be softened to allow a state to strike preemptively when there is a broad claim for “self-preservation”—as Israel claims against Iran, not without justification—even absent an imminent threat. Others have responded that the immanence criterion is necessary given the unpredictability and instability that always accompanies war.
In the ethical analysis, a requirement of immanence for preemptive strikes ties closely to the other just war criteria. Just war theory doesn’t suggest that war is ever inherently good. “War is Hell,” said William Tecumseh Sherman, who led the Union Army’s devastating March to the Sea during the Civil War. In the Christian intellectual tradition from which medieval just war theory developed, Sherman’s quip can be understood almost literally: War is intrinsically evil and unleashes upon the earth death, pain, and destruction we can rightly identify as “Hell.” It’s an evil that might have to be unleashed to prevent worse evils, but it’s still an evil.
The “last resort” criterion therefore strictly qualifies the “just cause” criterion. Even if there is just cause, all other reasonable options must first be exhausted. In the present war, no even remotely plausible rationale has been offered for why now, suddenly, diplomatic and other means have been closed down and the gates of Hell opened. The most we’ve heard is that some statements were made in a closed-door meeting that Steve Witkoff, the president’s envoy, interpreted as threatening or impertinent. We’re left to infer what is almost certainly the case: that our unstable, mercurial president acted on impulse when means far short of war still had a chance of success.
We have heard, alternatively (or in addition, depending on the day and hour), that our ally Israel planned to act regardless of our participation, so we decided it was better to join in than to leave them to go it alone. The antisemitic responses to this rationale on the far right have been loud and disgusting. Recognizing this pervasive neo-Nazi bile for what it is, Israel’s decision by itself doesn’t establish “last resort” either for Israel or the United States. If anything, the fusion of Israeli Prime Minister Benjamin Netanyahu’s political ambitions with President Trump’s fragile and volatile temperament should require even more compelling public evidence of “last resort.”
Instead, one of the public reasons offered for the war—that Israel was already committed to attacking—suggests that the decision to attack Iran was one of convenience, not necessity. And whatever the private reasons might have been, the public reasons matter because they relate to the criterion of “proper authority.” If war must be waged, it must be governed and limited by law, which means it can rightly be waged only by duly constituted legal authority. In established democracies, war is never lawfully the province of one person’s or one faction’s whim alone. Under the Constitution, only Congress possesses the power to declare war. This ensures that there is public debate about the casus belli sufficient to convince enough of the polity that war is just and necessary.
It is true—legally, historically, and morally—that the executive branch’s inherent responsibilities and powers must include some freedom to respond to immediate crises without a formal declaration of war. On the other hand, the suspension of the ordinary rule of law through emergency declaration is one of the first moves in the authoritarian’s playbook. The War Powers Resolution attempts to navigate this tension, and though it may be unconstitutional because of some of its specific provisions (as every president since Nixon has affirmed), it reflects the importance of this basic constitutional structure. Concerning this current Iran war, Congress—and, thereby, the public—has been neutered by the president’s unilateral action, without any prior meaningful consultation, debate, deliberation, or resolution. (Or, more accurately, Congress castrated itself.) This war therefore fails the “proper authority” criterion.
The next criterion, “right intention,” seeks to ensure that just war reasoning is not used as a screen for unjust purposes. This reflects the roots of just war theory in what we would today call “virtue ethics.” Just war reasoning is not merely consequentialist—i.e., whether a war is just does not depend solely on whether it has good outcomes. Supporters of this war ask, “How could anyone be against removing the evil Iranian regime from power?” But removing the evil Iranian regime (or an evil Venezuelan strongman, or a Cuban Communist Party secretary, or a Greenlandic prime minister) because you desire the country’s oil, rare earth minerals, or strategic location is unjust, even if there are otherwise threats that could justify military action.
This criterion raises difficult questions about mixed motives—whether a just motive merely must predominate when there are multiple motives, how to judge “intent” when multiple individuals and institutional actors are engaged, and so on. The reason President Trump’s Iran war fails this criterion is because we simply have no idea what the intention is, given the ever-shifting rationales provided. “Right intention,” at minimum, requires some intention beyond an arbitrary, unpredictable whim.
Finally, as to the Iran war, we can take reasonable chance of success and proportionality between ends and means together. A reasonable chance of success requires clearly articulated intent and careful planning toward realizing those intended objectives. What we have been given so far are constantly changing and conflicting reasons, ranging from the possibly realistic (surgical elimination of some military capabilities) to the unlikely (permanent elimination of nuclear threat) to the at-best quixotic, if not fantastical (total, enduring regime change). And this is all with no evidence of planning to achieve anything specific beyond what Defense Secretary Pete Hegseth called “death and destruction from the sky all day long.” These criteria, therefore, also have not been met.
Under just war reasoning, then, the current U.S. war in Iran is unjust, and therefore both unlawful and immoral. This is even before examining the jus in bello criteria of discrimination and proportionality, which would call into question some of the U.S. and Israeli targeting decisions and weapons choices, assuming jus ad bellum was satisfied.
Of course, one could adopt a realist perspective that talk of justice is meaningless and international law is a sham. We could agree, as Stephen Miller famously put it in the domestic context, that only strength, force, and power matter. And we could trust that Donald Trump, in the wisdom of his own morality without regard to legal or traditional just war norms, knows what he’s doing and will finally achieve peace in the Middle East. But an administration that is so obsessed with what it considers the protection of Western civilization should pay some attention to the just war theory that has become a key accomplishment of that civilization and has been enshrined in international law as a basic check against the horrors of war.
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