(RNS) — Hopefully you didn’t forget that there is (still) a war going on in Ukraine.

It isn’t just any war, of course, but a war of conquest perpetuated by Russia invading a sovereign nation. And it is a war that has seen massive numbers of unspeakable war crimes.

These war crimes have included, among other things, the intentional and systematic targeting of civilians. (Photos of the “liberation” of Mariupol reveal a large city that has been hollowed out of its people and infrastructure.) The evidence includes mass graves, intentional destruction of  hospitals, execution-style shootings of civilians, and, yes, horrific sexual violence.

Sexual violence is being explicitly used as a tool of war, not only to motivate the grotesquely evil soldiers who are raping Ukrainian women and girls, but also to subdue the population in the short term and impact Ukrainian birth rates in the longer term. Russian soldiers, apparently, hoped that “their captives would recoil from sex in the future and thus not bear Ukrainian children.”

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I hope that everyone reading these words is outraged that anyone could even contemplate (much less engage in) acts that are so evil. I can barely write them without feeling rage in my heart. The level of evil present in the acts is so overwhelming that one thought about whether anyone should ever engage in them is one thought too many.

But here is why academic arguments over ethical theory, though at times esoteric and deeply disconnected from reality, can be so important for the real world.

The ethical theory that dominates so much of our secularized culture — whether we are talking about medicine, whether we are talking about finance, and, yes, whether we are talking about foreign policy — is utilitarianism. This is the theory that explicitly says that all acts are in principle morally acceptable if they can produce the greatest good (pleasure, preference-satisfaction, happiness, etc.) for the greatest number of people.

Now, there are several deep problems with this ethical theory. There is, for instance, no way to peer into the distant future to determine what will in fact produce the greatest good for the greatest number. Human beings are notoriously bad at making these calculations — just look at the super confident and longstanding (but deeply misguided) worries about so-called “overpopulation.”

Ukrainian emergency employees and volunteers carry an injured pregnant woman from a maternity hospital in Mariupol, Ukraine, Wednesday, March 9, 2022. (AP Photo/Evgeniy Maloletka)

Also, some goods just cannot be compared with each other in ways that can be made to fit into a utilitarian calculation. Ethicists call this the “incommensurability problem.” We just lived through several examples of this problem in the early part of the pandemic.

How, for instance, should we have compared the utility of young children learning how to communicate through facial expressions versus the utility of masking children in school? How should we have compared the utility of the elderly not dying alone versus the utility of keeping healthy people away from those infected with COVID?

The answer is that these goods cannot be compared in any meaningful way — for the goods involved are incommensurable. But comparing them is exactly what utilitarianism requires.

Perhaps the central problem with utilitarianism, however, is that it cannot simply say an act is wrong because it is an act of injustice against another person. So, Russian soldiers executing or raping a 12-year-old girl might be wrong on this view, but one would need to first show that the act produces less utility.

Now, the best advocates for utilitarianism are what are sometimes called “rule” utilitarians. They agree that it is silly to make a comparison of net utility for every single act but instead insist that, over time, we have learned which rules produce the most utility. It is bad to execute or rape a 12-year-old girl, not because it violates fundamental justice but because — in the long run — it will produce less utility than if we didn’t have a rule against it.

But it just isn’t clear that these practices don’t “work” in very similar ways to other kinds of tried-and-true war-time tactics. Indeed, Russia has been taught that these practices “work” in multiple circumstances, including the horror show of the war on Chechnya, in which they used the massacre of civilians in a “deliberate campaign to terrorize the population into submission.”

Ultimately, however, the question of whether killing the innocent and engaging in violent nonconsensual sex are wrong must not be a question of whether or not they “work.” Some acts are just so heinous, so evil, so utterly inconsistent with the good that they can never be done under any circumstances.

In my world of Catholic moral theology, we call them “intrinsically evil acts,” actions that have such evil, such grave evil, at their heart or object such that there can never be exceptions. Basic, fundamental justice and human dignity require that the act is always and everywhere deeply wrong.

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This doesn’t mean doing away with complexity and gray areas. Plenty of Catholic moral theologians who reject utilitarianism still engage in difficult moral questions on a host of matters, from abortion to save the life of the mother to the use of large doses of pain medication at the end of life to when one can legitimately foresee that one’s actions will lead to the death of the innocent without intending that death.

But the horrific war crimes perpetrated by Russia should be yet another reminder of the morally impoverished vision of utilitarianism. We must stand for fundamental justice in ways that deem certain actions always and in every circumstance deeply, profoundly evil. And this means rejecting utilitarianism in favor of fundamental justice, especially for the most vulnerable.