Syrian girl Noor, famous for broadcasting clips on social media about the regime-bombardments on Eastern Ghouta, after being evacuated from Arbin in March 2018.Zein Al Rifai / AFP / Getty Images

For seven years now, America has been struggling to understand its moral responsibility in Syria. For every urgent argument to intervene against Syrian President Bashar al-Assad to stop the mass killing of civilians, there were ready responses about the risks of causing more destruction than could be averted, or even escalating to a major war with other powers in Syria. In the end, American intervention there has been tailored mostly to a narrow perception of American interests in stopping the threat of terror. But the fundamental questions are still unresolved: What exactly was the moral course of action in Syria? And more urgently, what—if any—is the moral course of action now?

The war has left roughly half a million people dead—the UN has stopped counting—but the question of moral responsibility has taken on new urgency in the wake of a suspected chemical attack over the weekend. As President Trump threatened to launch retaliatory missile strikes, I spoke about America’s ethical responsibility with some of the world’s leading moral philosophers. These are people whose job it is to ascertain the right thing to do in any given situation. All of them suggested that, years ago, America might have been able to intervene in a moral way to stop the killing in the Syrian civil war. But asked what America should do now, they all gave the same startling response: They don’t know.

The usual framework philosophers would use to answer this question—the so-called just-war theory—isn’t providing clear answers. The theory’s first principle is that if you’re going to go to war, you need to have a just cause. At this point, the humanitarian crisis in Syria is so severe that most people would probably agree that condition has already been met. And that was true before the weekend’s suspected chemical attack. The ethicists I spoke to said the death toll alone could establish just cause; the use of chemical weapons could add a further element of moral responsibility to stop it, not so much because of the pain they cause, but because they kill indiscriminately, wiping out combatants and civilians alike. Conventional weapons, like barrel bombs, also kill indiscriminately.

But there are other conditions that have to be satisfied for a war to be considered just or moral. One is that an intervention has to achieve more good than harm. And it’s not clear, according to the ethicists I spoke to, that any military action the United States can take in Syria now will fulfill that condition.

“As a utilitarian, I’m concerned about the consequences,” said Peter Singer, an Australian moral philosopher famous for his work on everything from the ethics of war to animal rights. “I think now the main question is, how can you achieve something that clearly has greater positive results than the harm it risks inflicting? The risks seem to me to be very serious.” A strike big enough to truly change Assad’s calculus risks causing more civilian deaths, or an escalation in the conflict. The latter risk is particularly grave given Russia’s involvement, as a Kremlin spokesman has explicitly warned. “If you could hold Assad or whoever responsible without risking harm to many other innocent parties, then that would be the right thing to do. But I can’t really see how it’s going to be done.” For instance, the Syrian government claimed that Trump’s strike on an airfield in response to last year’s chemical attack killed 15 people, some of them civilians, and chemical attacks continued—meaning that lives were lost without the “positive result” of stopping them. The more costly the response to Assad, the more costly it might be to his people as well. The question is whether the lives lost in the response would be fewer than those lost without one.  

The just-war theory also stipulates that a rightful intervention must have a reasonable chance of success. That, too, seems unlikely here given how the response played out last year, according to Helen Frowe, a philosopher at Stockholm University who specializes in the ethics of war and foreign intervention. I reached out to Frowe because she’s taken a strong stance on philosophy’s famous Trolley Problem: She argues that if you can flip a switch and redirect a runaway trolley so that instead of killing five people it will kill only one, you’re not just permitted but actually morally required to do so. Many would argue that the United States had a moral requirement, then, to risk some Syrian and American lives earlier in the conflict if there was a chance of stopping the massive loss of life that has occurred in the intervening years. But what does that mean today? I asked Frowe if she thinks Trump striking Syria now would be akin to flipping that switch.

[Readers respond: ‘And Now, Now Will We Go to War?’]

“I think that when you know you’re able to save a significant number of lives by causing significantly less harm, you’re required to do that. The problem is, I don’t think a strike now is going to save any lives,” she said. “The last time Trump did that, it clearly didn’t prevent the regime from using chemical weapons.” Similar strike options are reportedly under consideration now.

At this point, she added, a strike “shows our distaste for the chemical attack, and it’s a show of force. And those are things that it’s good to do—but it’s not good to do it by killing people.” When I asked Frowe what she thinks it would be good to do—what she would do if she were president of the U.S. right now—she said, “Christ, I don’t know.”

Nancy Sherman, a philosopher who teaches at Georgetown University, had a different answer. “If I were president, I would probably have some limited strike to avert chemical-weapons use.” But Sherman was more interested in emphasizing another requirement of just-war theory: The intervener has to have the right intentions. As a virtue ethicist, she focuses on a person’s inner moral qualities, so intentions are particularly important to her.

Sherman cited Aristotle, the father of virtue ethics, who encouraged people to look to role models—rather than a rule or formula—to figure out how to live ethically. The leader of a polity in particular is expected to be an ethical exemplar, someone who models virtuous intentions and behavior. “Trump is an extremely troubling moral leader,” she said. “One doesn’t know what his intent is other than self-aggrandizement or publicity. Whether or not he’s interested in the cause of justice is very much a question.”

Sherman acknowledged that it’s possible for a leader to do the right thing for the wrong reason. But if he’s not imbued with virtuous intentions, he may get one action right and yet be likely to get the next several actions terribly wrong. She said that although she herself would probably order a targeted strike if she were president, the difficulty of establishing right intention in Trump’s case “tempers my view that, in general, a strike that would deter future humanitarian tragedy is justified.” That doesn’t necessarily mean it’s not justified. But when Sherman was asked whether today’s America—the one that has Trump as president—should intervene against Assad right now, she said, “Oh boy. I don’t know. … I really don’t know.”

All these “I don’t knows” raise another ethical question: What do you do if it’s just too late to do the right thing—if the trolley has already careened past you and the switch, unflipped, is useless under your hand?

Previous wars have confronted the international community with this question. After World War II, many asked how leaders could have stood by and watched as the horrors of the Holocaust brought millions to their deaths. The prevention of genocide and mass atrocities became an urgent field of study. Yet the world kept failing to respond in time to stop genocides such as Rwanda’s and massacres such as Srebrenica’s.

A turning point came in 2005, when UN member states committed to the doctrine of Responsibility to Protect, which imported many principles from just-war theory. By endorsing it, world leaders agreed that they have a duty to protect their citizens from atrocities and to take action in foreign countries when leaders there fail to protect their own citizens. Today, some defend this global political commitment as the best tool currently available to mobilize the international community against atrocities, but others argue that it’s legally unenforceable and therefore ineffective. In Syria’s case, it clearly hasn’t helped. Military or any other action cannot legally be undertaken under the Responsibility to Protect doctrine in a given country without the approval of the UN Security Council, and Russia and China blocked its application in Syria years ago. “That was a very tragically missed opportunity,” Singer told me.

If there’s no clear moral answer to the question of what America should do in Syria, the people I spoke to said there are still moral things it can do for Syrians. America can respond ethically by improving its policies toward refugees who have already fled Syria (so far the U.S. has welcomed in a relatively paltry number), or by focusing on reconstruction and trying to enforce the international Chemical Weapons Convention after the conflict is over, Frowe said. But as far as what America can do in Syria now? The just-war requirements make it hard for any philosopher to build a moral case for late-stage intervention. A moral case against it is easier to build, because the burden of proof is on the would-be interveners to show they satisfy all the conditions for a just war—and at the moment, the evidence for that seems weak.

“One of the lessons to be learned is that we need a better plan for intervention earlier, one that might have some prospect of success,” Frowe said. Otherwise, “you can end up in a situation where you have no good options—where there’s nothing that it’s permissible for you to do.”

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