The Decibel - International law in the Trump era

Episode Date: January 16, 2026

In less than a year, U.S. President Donald Trump’s second term has re-shaped the international order. From levying tariffs against much of the world, turning against long-standing allies, capturing Venezuela’s president, and threatening to annex Greenland – the U.S. has flouted international law and ignored the traditional rules-based order.Michael Byers, Canada research chair on global politics and international law at the University of British Columbia, is on the show to explain the legal agreements and treaties that govern the international order and whether it’s possible to hold powerful countries to account when they defy those laws.Questions? Comments? Ideas? Email us at [e-mail] Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.

Since beginning his second term almost a year ago, U.S. President Donald Trump has been reshaping his country's relationships with the international community. He upended global trade norms by imposing unpredictable tariffs across the board. He attacked Venezuela and seized its president. And lately, he's renewed his threats of annexing Greenland. In a recent interview with the New York Times, reporters asked him if there were any limits to the power he's exercising on the global stage. checks on your power on the world stage? Is there anything that could stop you if you wanted to? Yeah, there's one thing.

My own morality, my own mind. It's the only thing that can stop. Not international law. And that's very good. I don't need international law. I'm not looking to hurt people. When pressed further on whether his administration needs to abide by international law, he said,

Yeah, I do. I, you know, I do. But it depends what your definition of international. law is. So today, we're going to define international law. Professor Michael Byers is our guest. He's the Canada Research Chair in Global Politics and International Law at the University of British Columbia.

He'll explain the complex web of rules and customs that make up international law, why we have them, and how much they still matter, as the Trump administration tests the limits of the system. I'm Cheryl Sutherland, and this is the decibel, from the Globe and Mail. Professor Michael Byers, thanks so much for coming on the show. It's great to be here. Thank you. So I want to start kind of basic here and kind of define what international law is,

because it's not just one set of laws, right? There are many institutions and arms. So can you help me understand how we should be thinking of it? Well, international law is made up of rules that are created by nation states for nation states. And so they go back some of these rules centuries to the fundamental rules establishing the principle of state sovereignty, the inviability of borders. International law has developed a lot since the 17th century. Today we have literally tens of thousands of rules, thousands and thousands of treaties. It's a complex legal system.

But the key point is that it was created by nation states to govern themselves. Can you kind of explain that a little bit more? by nation states to govern themselves. Basically, it's like laws between them, right? Exactly. So international law is based upon enlightened self-interest. It has developed because hundreds of governments, national governments, have recognized that they all have an interest in stability and predictability

to maximize their commercial opportunities, to reduce the amount of money they need to spend on defense, to facilitate the travel of their citizens, that it makes sense to have rules that everyone has agreed to. I often describe international law like an iceberg, right? That 90% of international law is hidden below the surface, and we never notice it because it works really, really well. So I had a cup of coffee this morning,

and we don't grow coffee in Canada, right? The only reason I'm able to buy coffee in Canada is because we have international treaties that allow for international trade. And no one thinks about international law when they're getting on an airplane or showing their passport at customs and immigration. But it goes on and on and on. So again, 90% of international law we never notice because it works. And all of our attention focuses on the top 10% or the top 5%.

The rules governing the use of military force. Human rights, which are, of course, being blatantly violated in places like Iran as we speak. we focus on the stuff that is controversial and where certain actors are breaking the rules. Where does the system come from? I mean, the father of international law is often considered to be a Dutchman named Hugo Grosius, who wrote a book on behalf of the government of Holland and the Dutch East India Company advocating for global acceptance of the freedom of the seas, the freedom to travel to trade across the world's oceans. And he was opposed by an English

international lawyer named John Selden, who argued that the seas should be closed off and subject to national jurisdiction, just like land. So, you know, it's not that countries always agree, but there's an interaction, there's a negotiation, and over time a lot of rules are adopted because countries make compromises. They want to get things done. They want to protect themselves and advance their interests. And so diplomacy and law are very closely linked to a lot of the work that diplomats do involves negotiating international treaties. Interesting. Okay. And you mentioned something earlier about sovereignty, and I kind of want to talk about the very core principles of international law. What would be kind of like a list of the core principles here?

Well, in the aftermath of the Second World War, the United States hosted a conference in San Francisco, where 50 national governments together negotiated and adopted the United Nations Charter. Okay. And the United Nations Charter was based upon preexisting rules and informal norms, but what it says at its core is that states are prohibited from threatening or using force against the territorial integrity or political independence of other nation states. So in other words, you can't just invade Venezuela and abduct the de facto head of state. That's prohibited under the United Nations Charter.

And a whole bunch of other rules developed during that same period. In 1948, nation states came together and adopted the genocide convention, prohibiting the systematic extermination of the people. And we also at the same time had the adoption of the general agreement on terrorist. and trade, which later became the World Trade Organization. We had the creation of the World Bank, the International Monetary Fund. A lot of the institutions that we take for granted today were built through negotiations by dozens, sometimes hundreds of states acting in their enlightened self-interest. Interesting. Let's talk about enforcement and how this all works. So first off, how do international

rules get made? Well, there are two main kinds of. of international law. The one that most people know about comes in the form of treaties, which are sometimes called charters or covenants or even memoranda of understanding. But if there are a written instrument intended to create rights and obligations between states, then there are a treaty. And there are tens of thousands of treaties. But there's also unwritten international law called customary international law. And this develops through the behavior of countries over time, coupled with some sense of legal obligation or at least legal relevance. And some of the core rules of international law are actually found in customer international law

because they're so fundamental and so obvious that they don't need to be written down. So the rules concerning the liability of nation states for their actions, those are rules of customer international law. And you know, that's not so different from some domestic legal systems. Most people don't know this, but the United Kingdom doesn't have a rule. written constitution. The British constitution is a set of unwritten, informal rules that everyone understands. Yeah. And countries have to choose to be part of these agreements or bodies, correct? They do. The system is based upon consent, but consent can be expressed through

inaction, through acquiescence. So if there's a new rule developing of customer international law, for instance, and you don't say anything, they're okay with it as a national government, then you can end up being bound. It's an opt-out system rather than an opt-in system. With regards to treaties, many treaties require that countries ratify them before they become legally bound. But some treaties can be amended at international organizations, and then every state that doesn't object is bound by the amendment.

So it's, again, an opt-out system. And to make the system work, to enable the adaptation of rules, to new circumstances, everyone's agreed that it's okay to flip the presumption to say that if you don't object, you will be bound. And it's not a problem because the fundamental principle that sovereign states have to consent to new rules is still upheld. Okay, so this makes me think about enforcement of these laws. And before we get into the international legal system, can you tell us what countries can do when another country breaks these rules? What happens?

Well, take Russia, which invaded Ukraine in February 2022. That was a massive violation of the most fundamental rule, which is the prohibition on the use of force against a sovereign state. But it's also true that Russia is a very powerful country. It has a nuclear arsenal. And it's difficult to enforce the rules against a country that could literally destroy humanity. And so Western countries chose not to send troops to fight alongside the Ukrainian military. They didn't want to push Russia that hard. But over the course of the last three years, Western countries have provided hundreds of billions, maybe trillions of dollars in support for the Ukrainian military in the form of weapons, in the form of satellite services, in the form of intelligence.

a massive transfer of funding and equipment to enable the Ukrainian military to push back against one of the most powerful armies in the world. And the fact that Ukraine is still a sovereign democratic state is a reflection of the enforcement of international law. Now, if Russia was a weaker country, if Russia didn't have nuclear weapons, then there might have been a harder form of enforcement, such as occurred after Saddam Hussein invaded Kuwait in 1991, where the United Nations Security Council authorized states to go and remove the Iraqi army from Kuwait, the first Gulf War. But you're not going to do that against a nuclear

power like Russia. So instead, you supply the weapons to the country that's been invaded, and on top of that, you adopt wide-ranging sanctions to squeeze the Russian economy to punish them in that way. Yeah, and Russia also becomes kind of a pariah, right? Like you talked about sanctions, there's suspending diplomatic relations. So there are, you know, things that countries can do on both ends by supporting one side and also by deterring the other. So the international legal system does have its own courts when things get very bad. Can you explain the International Court of Justice?

How does that operate? So the International Court of Justice was created by the United Nations Charter. at that conference in San Francisco in 1945, and it is the judicial body of the United Nations. But it can only hear cases where the two national governments have consented to the court having jurisdiction. And sometimes two countries want to resolve a dispute, and they go to the court, and they say, help us out. Can you give us a legal ruling? But more often, countries agree to the jurisdiction of the court with regards to a treaty that they're ratifying and that treaty will have a dispute resolution provision that says in the event of any disagreement about the application

of this treaty, the parties to this treaty agree in advance to the International Court of Justice ruling on the dispute. And sometimes, you know, countries get surprised. So the government of Benjamin Netanyahu in Israel was surprised when South Africa went to the International Court of Justice and said, we want to initiate a case against Israel under the 1948 genocide convention. And at that point, the Israeli Foreign Ministry probably dusted off its old copy of the genocide convention and realized that when they'd ratified it, they'd agreed to the jurisdiction of the International Court of Justice. So 70 years later, that act of ratification came back to bite.

the government of Benjamin Netanyahu, which then found itself having to defend its actions in Gaza. So a lot of what international lawyers and foreign ministries do is to try to identify in what treaties and what instances are they actually open to being taken to the International Court of Justice or in what situations could they take another country to the International Court of Justice And jurisdiction and finding jurisdiction and establishing jurisdiction is one of the really important things that all these lawyers do. And what happens when they do? Is there consequences? Well, I've had a lot of concerns about the Netanyahu government, but I will congratulate them for sending a superb team of international lawyers to defend Israel's actions at the International Court of Justice.

Because they don't have to, right? Well, in some cases, countries just don't show up, right? Yeah. But Israel showed up. And this is important because by showing up, by sending their lawyers to defend themselves in court, they are reinforcing the validity of the international legal system, right? Or to give you another example, when governments torture people around the world, they always deny and seek to conceal what they're doing. I mean, no country admits to torture. And by denying and concealing that they're doing it, they're actually strengthening the system.

It's the tribute that vice pays to virtue. That act of denial and concealment, it makes the rules stronger rather than the act of torture weakening the rule. We'll be right back. So we talked about the ICJ. What about the ICC, the international criminal court? How is this different? The international criminal court was created in 1998 and Canada played a huge role. They persuaded countries to come together in Rome for a treaty negotiation to adopt a treaty where the focus would be in bringing the individuals to justice to identify people who had committed or were alleged to have committed specific crimes that already existed in international law, the prohibition on torture, the prohibition on genocide, the prohibition on targeting innocent civil.

civilians during warfare. We had those rules already by 1998, but we didn't have a mechanism for going after the perpetrators. And so they created a court that would go after the perpetrators. It built on a few previous experiments, the International Criminal Tribunal for the former Yugoslavia, the International Criminal Tribunal for Rwanda, but it was more ambitious. It wanted to deal with the whole world. And it was a tough negotiation and powerful countries like the United States pushed hard to try to protect themselves. They weren't going to ratify this treaty, but they participated in order to protect themselves. And so the compromise was that the international criminal court only has jurisdiction with regards to the nationals of a country

that actually ratifies the court statute or crimes committed on the territory of a country that has ratified the statute. And the United States thought that was okay. But it turns out that some countries unexpectedly ratified the statute and thus gave jurisdiction with regards to crimes on their territory. And that included Afghanistan. And then later, it included Palestine. Also includes the Ukraine. And so powerful countries like the United States, Israel and Russia, found themselves engaged in military action on territory that was subject to the jurisdiction of the International Criminal Court. And the ICC has issued arrest warrants against Vladimir Putin

and against Benjamin Netanyahu and was investigating the actions of American forces in Afghanistan up until a few years ago. So even the powerful can get caught up. So at some point, Vladimir Putin won't be president of Russia anymore. And if he hasn't been pushed out of a window, it's quite possible that he'll be shipped off to the Hague. Okay, so let's talk about the United States.

The U.S. played a key role in creating this international legal system. What do you think is different about the way this administration, the Trump administration, view international law today? This second Trump administration is populated at the highest levels by people who have no apparent sense of history and no respect for expertise. And so you have people like Pete Hegseth, who is currently the Secretary of Defense, who has fired the top career lawyers in the U.S. Department of Defense because they were trying to limit war crimes ordered by Hegseth. So, for instance, the targeting of these small boats in the Caribbean and the Eastern Pacific. We have Donald Trump being interviewed by the New York Times, you know, saying that international.

National law is not a constraint on him. The only thing that constrains him as U.S. president is his own morality. And there's never been any previous U.S. administration that took this view. And I include the administration of George W. Bush, which did violate some fundamental rules, but still understood that there needed to be a legal system, right? The reason I say this is because every U.S. administration, going back to 1776 has seen a value not just in tying its own hands, but tying its own hands so that it could thereby tie the hands of other countries, that it could create stability and predictability, and that there was a real advantage to the United States in terms of leading the creation of a legal system, of being the most effective negotiator in a treaty negotiation.

Every administration has understood that. more than others. Are the rules different for the superpowers? Do they face the same level of consequences when they break international law? Not the same consequences, but they do pay a price. And so, for instance, they can face sanctions. Or as a Russian diplomat once said to me, the worst thing about us violating a rule of international law is that we don't get invited to any of the diplomatic receptions for the next year or two.

That sounds silly. But if you're a diplomat, where do you practice your trade? Where do you have those important conversations? Well, it's at the receptions. It's during the coffee breaks. It's over a glass of vodka in the hotel bar. That's where diplomacy takes place. It's a very powerful sanction, and it's underestimated. But the thing about powerful countries is that they do want to have influence. They do want to shape the system. They want to have power that's not just defined by guns and bombs. And all of a sudden, they find themselves excluded. But the possible anomaly that exists right now is that the Trump administration almost seems to want to be a pariah state, right? Because it completely misunderstands the complex nature of power. It literally thinks that

it can use economic and military pressure to coerce anyone else to do what it wants, or at least any country that doesn't have nuclear weapons. And it's striking how Donald Trump plays nice with Russia and China, but then picks on his closest allies like Denmark or Canada. You know, this is the behavior of a bully who doesn't see the long game. And I think that they will find out fairly quickly that there are real costs associated with burning up friendships and destroying trust. Let's bring in Canada here for a moment. Prime Minister Mark Carney released a statement that included a call for all parties to, quote, respect international law following the U.S.'s. attack on Venezuela. What role could or should

Canada play if countries like the U.S. don't respect international law moving forward? And how should Carney balance addressing this with ongoing trade negotiations with the U.S.? We still have to do business with the U.S., but Donald Trump isn't going to respect the U.N. charter? Why would he respect a free trade agreement? Right? I mean, how much faith that are we putting into negotiated agreements with someone who's becoming a serial violator of international law. Donald Trump is a bully. The strategy of playing nice just doesn't work with a bully, because they'll just come back for more. So the strategy is to make sure you have friends and bring your friends close, and then you speak with a collective voice, right? The way you deal with

Donald Trump is to coordinate closely with like-minded countries. We should be getting ever closer to our NATO allies in Europe. We should be getting ever closer. to South Korea and Japan and Australia and Singapore and other countries. We need to build those alliances. And I think Mr. Carney gets that, right? But being timid and quiet is not how you deal with a bully. And I'm not saying that we should go out trying to pick fights with Donald Trump. But when he does something that is seriously contrary to our interests,

we should raise an elbow just a little bit and say so. Let's coordinate closely with our allies. you know, when Trump or any other world leader does something seriously wrong, let's issue joint statements and partnership with other countries, which is what the Europeans did with regards to Greenland a few days ago. We are stronger together. Donald Trump knows this. I mean, Donald Trump tries to isolate countries. He deals with them one-on-one. He focuses his power on a single country to get what he wants. And the strategy always is to go multilateral, to go collective, to bring our friends together with us.

I'm glad you brought up NATO because there is a real test to NATO right now when it comes to Greenland and the U.S. threatening to annex Greenland, right? Are you suggesting that Canada helps lead the creation of, I don't know, a NATO without the U.S.? Only in the situation where the United States invades Greenland. Because that's untenable. That would be one NATO state attacking another NATO state. And that configuration of the alliance is at that point fatally compromised. But the world is always changing. And international law and international institutions are always evolving.

So there's nothing to stop the other 31 NATO states from saying, okay, we're going to create a new NATO without the United States. And I would suggest that if we end up having to do that, that we then invite South Korea, Japan, Australia, New Zealand. Brazil, South Africa, right? We are stronger together with other democratic states that don't want to have superpowers gratuitously invading other countries. Would that be challenging? Absolutely. Would it be difficult? Absolutely. Is there any other rational path forward in a situation where one NATO country grabs a piece of another? I don't think so. What a time we're in right now. I tell my students that if you can stop being terrified, this is all extremely interesting. Michael, this has been really interesting.

Thank you so much for coming on the show. Thank you. It's been fun. That was Professor Michael Byers, the Canada Research Chair in Global Politics and International Law at EBC. That's it for today. I'm Cheryl Sutherland. Our producers are Madeline White, Mikhail Stein, and Ali Graham. Our editor is David Crosby. Adrian Chung is our senior producer

and Angela Pichenza is our executive editor. Thanks so much for listening.