The Legal Front of the Russo-Ukrainian War: an Interview with Harold Hongju Koh

By Ted Shepherd


Harold Hongju Koh is Sterling Professor of International Law at Yale Law School and one of the leading experts on international law and national security law. He served as the Legal Adviser of the U.S. Department of State during the Obama Administration, earning the Secretary of State’s Distinguished Service Award for his service. Professor Koh served as the Dean of Yale Law School from 2004-2009. In addition to being a prolific and renowned scholar, he regularly testifies before Congress and litigates international law cases in both U.S. and international tribunals. He has received more than 30 awards for his human rights work, including two lifetime achievement awards in international law. 


In March 2022, Professor Koh argued at the International Court of Justice (ICJ) on behalf of Ukraine in the country’s recently-filed case against Russia. Soon after Koh’s closing argument, the ICJ ordered the Russian Federation to immediately cease its military operations in Ukraine. Professor Koh is also involved in Ukraine’s 2017 ICJ case against Russia over the latter’s invasion of Crimea. I had the opportunity to interview Professor Koh about the ICJ cases and the implications of the Court’s recent ruling for the international legal order.



Could you give our readers a brief description of the International Court of Justice case and of your involvement in it?



There are actually two cases, both Ukraine against Russia. The first began in 2016 and it concerned terrorist activities supported by the Russians in the Eastern Ukraine region of the Donbas–and whether this violates an international convention for the suppression of financing of terrorism. The other half of that case is about racial discrimination against indigenous Crimeans and Ukrainians in Crimea based on the Russian occupation. We’ve been working on this case for years and it’s gone to the merits. We’re waiting to have a hearing on it, and we’ve submitted all the documents. But while we were working on this case at the end of 2021, we asked our client, the Ukrainian Government, “What would you do if Putin invaded you?” They said, “We’d probably like to file another lawsuit. Do you have a theory for what we could do?” We said “Yes, if he continues to say that the Ukrainians are committing genocide in Ukraine, which is clearly false, then we could bring a case arguing that these are false allegations of genocide against Ukraine that form the basis for Russia’s illegal use of force. This would have the advantage that we could get before the Court very quickly to get a preliminary ruling saying that any activities of the Russians in the territory of Ukraine are illegal. We ended up bringing that suit and got the ruling on March 16. As a result, everything the Russians have been doing since is illegal by order of this court. Now, some people say the court can’t enforce its own ruling. But no court can enforce its own ruling. The point is the court can say what is legal and illegal. When one person called the court’s ruling “purely symbolic,” I asked him. “Do you think what the Russians are doing is illegal?” He said, “Yes.” I said, “How do you know?” and he gave a bunch of reasons. And I asked, “Is it because the International Court of Justice ruled on March 16 that it is illegal?” He responded, “Well, yes, that has a lot to do with it.” We got a very early declaration of illegality, and now the question is how to use it to weaken the Russian position and isolate them and hopefully, combined with the military efforts, get to a better outcome.



Are you expecting Russia to appear in the next hearing? 



Yes. The Russians didn’t appear in the hearing we had on March 9th. Their lawyers quit, because ethically they could not defend the invasion. But Russia has subsequently filed a number of pleadings which suggests they got new lawyers. We’re not sure who they are, but the papers show they’re making more sophisticated legal arguments so they’ve obviously found somebody. I assume those people will appear, along with Russian government lawyers. 



Do you have any other forecasts about the future of the ICJ case? Do you think there will be Security Council implementation of the decision, for example?



Well, we just got a General Assembly vote a couple days ago, 143 countries condemning the annexation of the 4 provinces as illegal, which I think bolsters our case. We’re in the zone of what’s called the “Uniting for Peace Resolution” which was used to authorize U.N. action in Korea, despite vetoes that paralyzed the Security Council. Obviously, the Russians and the Chinese were vetoing the Security Council resolution, so this is a return to an earlier time. From 1987-88 to 2010, the Russians played ball and didn’t veto everything. But then in Syria, they started vetoing everything. A lot of what international lawyers did during the Cold War was to figure out lawful ways around their veto. So, we’re back where I was at the start of my career. 



I’ve read that people describe this period from 1991-2011 as this peculiar unipolar moment where the liberal order and international courts of justice had sway, but that, before that, during the Cold War, and now today, when there is competition among the great powers, that the courts won’t be as influential. What is your take on that?



Well, law and politics have to work together. And lawyers have to figure out legal strategies that bolster the political position they’re trying to achieve. The Russians are openly defiant to the rule of law. But as I said in the argument, Putin’s short game is force. The world’s long game is law. That’s going to take longer, but the Russians need to be part of an interdependent world, and they can’t do it if they’re an outlaw. There’s a five-part strategy here: illegality, isolation, information, accountability, and diplomacy. First, declare all the actions of the Russians illegal. If they do them, it leaves them more isolated. The fact that neither the Indians nor the Chinese have openly backed Russia shows that they don’t want to be on the wrong side of the law either. And then information—use open sources to show exactly what the Russians are doing, to combat their fake news. And all of social media is working on the side of the Ukrainians right now. And then you have open dissent within Russia, especially about their draft. Hopefully this will lead them, eventually, to a position of diplomacy where they agree to a cease-fire. Where they try to figure out the future. And, within that ceasefire, we keep accountability alive. In other words, don’t let Putin bargain for his own amnesty. That’s the long-term strategy. The question is how to maintain commitment to that strategy over the long term. This legal strategy has also turned crucially on the Ukrainians not being beaten on the battlefield. Putin obviously is going to be more inclined to go into diplomacy if it’s not going well on the ground. And it’s going terribly for him on the ground right now.



China hasn’t come out in support of Russia, as you predicted after the ruling, and has recently called for peace talks. Do you think the ICJ ruling played a part in this?



China had a different strategy which Putin upset. They wanted to use their economic power to create an alternative system to the Bretton Woods system. They wanted to create a “belt-and-road” initiative and an Asian Development Bank which they fund and then use their money to buy off non-aligned countries. But they don’t want to adopt a position of open illegality. And their claim is that whatever they’re doing in Xinjiang against the Uyghurs is an internal affair. In the middle of this comes Putin. Putin went to China during the February 2022 Winter Olympics, and they clearly asked him, “Don’t invade during the Olympics.” And he didn’t, but he invaded soon after. And at the most recent meeting between Xi Jinping and Putin, Xi said “I don’t know what your endgame is, but it’s not working for us.” They want to be members of the World Trade Organization. So, they’re saying things that are critical of the West, but they’re not backing Putin. And he desperately needs their help. And the same with the Indians: Modi is even more direct in rebuffing Putin. So Putin’s isolated abroad, and now he’s called up a draft. As yesterday’s New York Times reported, these men are being sent to the front with no military training, and their families are incredibly upset, as you can imagine. At some point, they have to say, “How did we get into this mess?” And the answer is Putin. Putin wasn’t satisfied with occupying Crimea. He had to do more. And, even more than that, he had to back his aggression with atrocities which make Russians war criminals. And the average Russian doesn’t want to be thought of as a war criminal. They view themselves as victims of war crimes in World War II, which is why they participated in Nuremberg. So, you can sense it’s not going the way Putin wanted. We just have to hang on and keep doing what we’re doing. Putin also “succeeded” in getting NATO extended to now include Finland and Sweden, which is an amazing accomplishment. You can understand what Putin thought. He sees Donald Trump, he sees Boris Johnson. He thinks the West is weak; they can’t get their act together to respond. He thought, if I do this, I’ve got China and India on my side, it will go fast, and it will be like Crimea all over again. But the game plan didn’t play out as he thought. And now he’s paying for his miscalculation. 



Does the US submitting a Declaration of Intervention in the ICJ case signify anything?



Yes, they are one of many countries that did so. The important thing is that this is not Russia against Ukraine. This is Russia against the international legal order and these interventions show that Ukraine is not by itself. It has all of these “rule of law” countries supporting it. 



In an international system that many political theorists see as characterized by anarchy, what in your view is the role of international law and courts? Can courts be useful when there is no centralized authority capable of executing their orders, or do you reject the idea that countries exist in a state of nature towards each other?



I reject that. We’re not living under a world government, but we’re not living in anarchy either. There’s a system of rules, norms, and institutions that have been created, particularly since World War II—the UN Charter and the Bretton Woods system—that distinguish between legal and illegal activities in the global realms. So, is that as well defined as a domestic legal order?—no. But it’s not anarchy. The real question is: can that system of the rule of law rally to sustain itself when it’s under tremendous stress. That means we have to fight to save the system we’ve created because we don’t have anything better. This is what has existed as long as I’ve been alive. Is it imperfect? Unbelievably. But if it falls apart, what have we got? We’d have to start from scratch. And then you’d still have to do alliance politics to organize countries for a collective response. What would you call that? A “United Nations” (laughing). So why don’t we keep the United Nations we have, try to sustain it and improve it. 



I’ve read many of the interviews you gave in March, immediately after the ICJ ruling, and you seemed very optimistic about the ruling and its effect on the war. Have the past six months given you any reason to think differently about the importance of the ICJ ruling? 



No, not at all. A couple of things have surprised me, but they’re all positive surprises. Number one—Zelensky is an extraordinary leader. People didn’t know much about Zelensky. He’s an actor, but it turns out his talent with the media and his resolve have really held the country in good stead. Among Ukrainians, he’s extraordinarily popular. Second, the Ukrainian fighting force, with the aid of Western weapons and support, is unbelievably effective. They’ve had victory after victory. Putin has a tremendous material advantage. He thought he was going to win by “shock and awe” in the first couple of months, and he hasn’t done so. An analogy I made early on was, “If someone gets fast-acting cancer, you don’t have that many options. You can do surgery or radiation, but the patient has to survive. And if the patient can survive, then there are all these other treatments, like chemotherapy, that can fight the cancer and put the person in remission and restore them to health.” And Ukrainians haven’t just survived; they’ve gotten the upper hand. They’ve used brilliant military techniques. For example, the Crimean resistance has done many things inside Crimea. There’s been many unexpected events like the blowing up of the Kerch Strait bridge. When the Russians left Kharkiv and went down the east coast, the Ukrainians came up behind them and seized back Kharkiv. The Russians haven’t made a lot of progress in acquiring territory, and they’ve suffered huge losses, including public relations losses, and they’re tapped out. Putin increasingly looks like a man in desperation. Look at what’s happened to him. His assets are frozen outside of Russia, his children can’t travel, he can’t travel, his oligarchs are also frozen. He’s like Pinochet in Chile—isolated in his own country. 



How would you respond to those who see hypocrisy in America’s involvement in this case about a country’s right to not be invaded, given, for example, our cross-border military activities in Kosovo and Iraq, neither of which were clearly authorized by the United Nations security council?



I think George W. Bush’s War in Iraq was illegal. We shouldn’t have done it and we’re paying the price for that. I think the intervention to protect and create an independent Kosovo was lawful and justified and the merits of that have been proven. But this kind of moral relativist argument can’t be used to justify what Putin is doing. Putin is engaging in a campaign of aggression and atrocity of the kind that we haven’t seen since World War II. It’s not just that they’re blatantly invading. It’s that they are killing everybody, including innocent civilians. From a distance, they fire shells indiscriminately. And up close, in places like Bucha, they just kill everybody. This is unbelievable. This from a country that signed all these treaties and that professed a commitment to human rights and the rule of law. But now, their rules of engagement are savagery and war crimes.  



In your book “The Trump Administration and International Law” you explained how transnational legal process — the idea that international law is actually a set of norms that becomes internalized and, therefore, binding under domestic law — could be used as a strategy to control the Trump administration’s flouting of international norms. Do you see this ICJ case as another example of transnational legal process at work? Or, do you think there is any argument that Russia’s invasion, in 2022, of a sovereign European country, is a refutation of your theory about norm internalization?



Yes, it does illustrate transnational legal process at work. It’s not over until it’s over. I believe this invasion will not hold. They’re going to have to walk it back. And it will be proof that they failed because of violation of the law and inadequate ability to carry out their aggressive objectives by force. I think this will go down in history as Putin’s fatal error. 



Do you think that this episode will make countries internalize the prohibitions on invasion and aggressive war, or will this be a turning point in which it will become more acceptable for countries to invade and engage in aggressive war? I’m thinking specifically of a potential Chinese invasion of Taiwan.



It depends on the outcome. It’s an existential moment. The rule of law has to win. We should not lose focus or get fatigued. This is the biggest challenge to the post-war legal order since 1945. There’s now a path forward that we can see, we just have to fight for it. Nobody gets anything without fighting for it. 



I’m lucky enough to be taking a class with Paul Kennedy right now, and I saw that you referenced him in the first chapter of your book “The Trump Administration and International Law.” You cited his ideas on “imperial overstretch,” referring to America. But do you think that Russia right now is overstretching its hard power, without enough soft power support, and falling into the same trap?



Oh, absolutely. What soft power does Russia have? Soft power turns on the perception that what they’re doing is legitimate. Instead, it’s viewed as a sham. Even their allies, Belarus and Iran, don’t believe it. They’ve sided with the Russians not because they believe their cause is legitimate, but because of some calculation of what sphere of influence they want to be a part of. 



To return to the subject of your aforementioned book, do you think Trump’s undermining of international norms and institutions precipitated Putin’s willingness to defy the international world order and disregard international law by using war crimes as a tool of aggression?



Yes. He said we don’t need NATO; he wanted to withdraw. The irony is that Putin’s invasion came when Biden is president and NATO is stronger than it’s ever been. It’s expanded to include Finland and Sweden, and other countries would like to join. It’s ironic that Estonia, with 1.4 million people, is part of NATO. So if they were invaded, Article 5 of the NATO treaty would mean all NATO members would come to their aid. But Ukraine, with 44 million and much larger territory, is not part of NATO. One of the issues being debated is whether Ukraine will ever become a member. Ukraine would like to join but that could end up being decided around the bargaining table. 


Since we spoke, many more European countries have joined the U.S. in submitting Declarations of Intervention to the International Court of Justice in support of Ukraine’s plea for help. The ICJ has issued provisional orders demanding that Russia ‘immediately suspend the military operations that it commenced on 24 February 2022 in the territory of Ukraine.’ The world now awaits Russia’s counter-memorandum, which is due on March 23, 2023. Then the ICJ will issue its binding final judgment. The Security Council is responsible for implementing the ICJ ruling, and Russia’s veto power will undoubtedly stop such an effort in its tracks. International experts like Koh, though, do not see this exercise in international law as futile. They think that the ICJ rulings — in conjunction with other rulings against Russia by international courts — have already been effective in gathering international consensus for the opinion that Russia’s invasion constitutes a violation of international law. 

Ted Shepherd is a sophomore in Pierson College and can be reached at