The war in Ukraine has united most Americans around the justice of the Ukrainian cause against a straightforward case of Russian aggression, while dividing intellectuals on both the left and the right who are accustomed to criticizing American overreach and military involvement. To get a thoughtful approach from a longtime critic of American war policy, Phil Klay, author of Redeployment and Missionaries, reached out to Samuel Moyn, a legal historian at Yale University and most recently the author of Humane: How the United States Abandoned Peace and Reinvented War.

Phil Klay: I wanted to talk to you about the war in Ukraine because, to be honest, I haven’t been especially impressed with some of the responses on the left, including from people who have been thoughtful about America’s wars in the past. There’s a kind of knee jerk-response that occasionally seems to rely not on careful thinking, but merely substituting one bit of war-justifying propaganda for another. How are you responding?

Samuel Moyn: I sympathize with the left’s knee-jerk response just on the grounds that it’s really important not to paper over Western hypocrisy in condemning war when we’ve started a lot of wars ourselves. And if you want to oppose the mainstream discourse, I would keep in mind first and foremost how this discourse is generalizing from a regional war to create a kind of Cold War framing which will be extremely relevant to how we respond to China down the road.

But beyond that, I think this is as naked an act of aggression as we’ve seen in some time. We can talk about how it is different from or similar to Putin’s prior wars and Western prior wars, but we are back in a situation where we have an oppressed people that is unlucky to be near a middle to great power. And it’s like a nineteenth-century land grab.

We care about the invaded and we should have solidarity with those facing down empires. We just have not figured out what to do to create a better international order that prohibits this sort of thing in the first place.

Your last book, Humane, carefully evokes the energy behind nineteenth-century antiwar movements, paying particular attention to the tradition of Christian pacifism, from William Lloyd Garrison to Williams Jennings Bryan to Norman Thomas. Do you think that tradition offers any lessons for the current moment?

I think it does, though our attitude toward the past has to be really discriminating. We shouldn’t idealize people merely because they may have something to offer us.

Many of the White Americans who dreamed of peace really meant that their country should stay out of European wars, maybe providing a Christian exemplar for the world but doing nothing, having no idea what to do about the fallen world symbolized by Europe’s internecine fighting. But these same Americans tolerated American wars in their hemisphere, and often worried about American expansion because of concerns about racial purity.

Even so, they did do something really important, which was to spark the idea that we could have an institutionalized peace, using law and politics to change the world for the better.

One of these early American peace activists, William Jay, the son of founding father John Jay, thought developing such an international system was the logical extension of the spirit of the Constitution, federalizing the world to, as he argued , do “for fractious nations what the Constitution had done for their previously fractious states in 1787.”

So you can trace a line from 1776 to Woodrow Wilson to the United Nations, and yet that kind of internationalism is often seen as a foreign imposition.

This is related to the evolution of American Christianity, in a way. Because for a lot of evangelical audiences lately the United Nations is the Antichrist – and was represented that way more crudely and influentially by Tim LaHaye, who in the Left Behind series is very explicit on this point.

Yet American history shows us that sovereign states can relinquish their sovereignty in the name of some higher, more perfect order. That’s also a huge rebuke to the so-called realists, like John Mearsheimer most famously, who suppose that there’s this unalterable thing called a state’s national interest. One must ask: Was that true of Virginia when it agreed to a federal scheme in 1788?

There was a price to pay, for sure, in federalizing. But the American tradition showed that it was worth it. That doesn’t mean transferring all power – though frankly, in my opinion Americans should have transferred more to the federal government in 1787 and to the United Nations in 1945.

Remember that some of these Midwestern senators wanted to join the United Nations Charter on grounds that it protects the Monroe Doctrine while making sure the United States itself can never get in trouble for its own wars. And we’re still living with their compromise because it’s not just the United States: Russia, too, can never get indicted because it has a Security Council veto.

And so I think we can draw on that that old insight, secular and religious, that states can give up power to create a more just and peaceful order.

So how do you get from an American Christian tradition deeply invested in international institutions to images of the United Nation as headed by the Antichrist?

Fundamentally, I think decolonization changes everything. Let’s remember that in 1945 the same peace activists we’re praising wanted a transatlantic, racially White peace, by and large, and they got it because that’s the way the world was. There were fifty-odd states in the early United Nations. Most of them were Latin American, so in our security zone, and then there were the Western allies, largely Western European, who would vote with our country.

And then everything changes, and parts of the organization are lost to the control of the old powers. Today you have four times as many states, the bulk of the new ones from Asia and Africa.

And, of course, you also have the collapse of mainline Christianity, which in the United States was really the source of most of those Americans who supported these ideas of world federation.

Sometimes international law is dismissed as an unenforceable fiction. There’s no world police force. Calling Putin a war criminal doesn’t seem to restrain him in any way. But early peace activists understood those limitations as well. Quincy Wright, one of the mid-twentieth-century peace actors you write about, described the law as “a term to conjure with,” since “many people will approve of a decision rationalized in legal terminology simply because it represents that holy symbol, the law.”

I don’t think you can disentangle the strength of the reaction to Ukraine from the norms propagated over the past centuries by those supposedly naive peace activists.

Of course it’s true that international law, like all law, is fictional. But as you know better than anyone, we live in our fictions.

The question is about what tools we have, rhetorical and otherwise. It’s really important not to idealize international law without checking what its results have been. Like all law, it still serves to entrench and legitimate a lot of unjust outcomes. But I see no alternative to reclaiming it to craft better ones.

Suddenly we’re in a world where Vladimir Putin, when he gives his irate speech justifying the war, appeals entirely to international law. He not only justifies his own aggression in terms of international law in ways that are incredibly flimsy, like many of America’s justifications for war lately, but he actually indicts the West for violating international law too. The universal language of debate is now this one.

Honestly, no one more than Putin has restored interest in aggressive war as a problem. That’s inadvertent on his part, but we should take advantage of the fact that he’s unpopular to create systemic changes, so that it’s not just unpopular leaders who pay consequences for violations, and never ourselves.

Marines carry their gear out to Army helicopters prior to an air assault into Marja, Afghanistan, Feb. 13, 2010 Photograph by Staff Sergeant Aubree Clute

What sort of systemic changes?

The basic one is the problem left unsolved in that era of the 1940s – what I call the “great-power peace.” There is a prohibition of war, but it only applies in fact to weaker powers.

Robert Jackson, the US Supreme Court justice who prosecuted at Nuremberg, indicts Adolf Hitler’s henchmen for breaching the peace but adds that this is not something we can only do to beaten enemies.

We have to revisit the veto in the Security Council. We can angle for the General Assembly to get more power in the United Nations, since it’s more representative. You could have the Rome Statute of the International Criminal Court revised to allow the General Assembly, and not just the Security Council, to refer cases.

And then there’s the reform that makes all the others possible, which is the kind of social mobilization concerned with world peace that was once prominent in the United States and which we’ve totally lost.

So there’s fixing international institutions, and also social mobilization to shift norms around war. Do you think the global sensibility about war has changed, and what opportunities does that open up?

It absolutely has changed. We’ve been talking about politics and law, but cultural revolutions are what change everything. Cultural and religious evolution, due to the prophets of a different future who spring up, affects the hearts and minds of millions or billions. Politics and law always turn out to be parasitic on those kinds of upheavals.

If there’s been a change since this early period we’ve been talking about, I think it has been about glamorizing war and American ideology. The last gasp of that Midwestern Christian pacifist tradition in America was George McGovern, who went down in a massive electoral defeat, and in response the Democrats developed these ideologies of beneficent war, and therefore beneficent military American power, which have led all the wars in our lifetimes to be romanticized at the start.

So I think we do need a cultural shift in favor of peace. It might not rule out war in desperate situations, but it can’t leave the world hostage to a peace of the great powers, backed by militaristic ideologies, which will mean such powers will go to war when and where they want, whatever the consequences. Ukraine is a testament as much to our collective failure as to Putin’s or Russia’s distinctive evil.

One of the revolutions in sensibility seems to be around discourse about human rights, which you’ve argued is specifically tied to mid-twentieth-century movements around the dignity of the person in Catholic and Protestant theology.

One of the interesting features of the middle of the twentieth century is that it’s a very Christian moment across many nations, in part because as the Cold War comes they’re facing the Soviet Union, which has arrogated secularism to itself.

One important fact about the more Christian human-rights moment of the 1940s is that human rights are conceived of as mostly depending on peace. The worst thing for human rights is when a war breaks out.

In the 1980s at the United Nations there was even a discussion of the possibility of having a human right to peace – but it died quickly and in part because the United States opposed it. What we’ve seen since, I think, is a new version of human rights that is untethered from peace, that indeed sometimes justifies war on the grounds that peace can sometimes entrench injustice. The trouble is that disrupting the peace usually makes things even worse.

This is the “humanitarian” argument for the Iraq War, for example.

The record of our time suggests, once again, that our ancestors were right to think that peace comes first, and if you want to advance justice you can’t do it through war.

One of the most interesting moments in the current debates occurred when the Kenyan representative to the UN said, look, postcolonial states had injustice baked in from the start, because they didn’t get to draw their borders. But, he continued, states like Kenya have renounced war, understanding that even wars for justice don’t advance it.

And I think this insight is one we’ve lost in the age of human rights, during which we have adopted a more warlike idealism that turns out not to make the world a better place, and sometimes a worse one.

In the midst of a crisis people often resort to more hard-edged thinking. Damir Marusic, a senior fellow at the Atlantic Council, has suggested that despite “a lot of dewy-eyed ‘fighting for our freedoms’ talk in the West,” this is “an existential struggle first and foremost, and Israel is the model for small states for the future, not universal values and belonging to the liberal world order.”

My basic response to Damir is that, when they’re not backed by superpowers, small states lose. And we shouldn’t accept a situation in which the agendas of small states depend on whether superpowers are backing them militarily.

We can also say there is a war happening in Israel on the territory of Palestine. It’s an occupation in fact or in effect. And should states be allowed to run occupations endlessly, in the way our country has waged an endless war on terror? Fighting for freedom often masks other agendas, and while it has its place (since there are some just wars in history), allegedly existential struggle brings out not the best but the worst more regularly.

Are there any organizations and institutions that you feel are doing a good job, advocating for the internationalism that you’d like to see?

I would point to much of the Global South, which endorsed with alacrity the General Assembly’s condemnation of Putin while often staying out of the sanctions regimes. You look to the weaker actors in a system, not because they’re better by nature or because they necessarily have better ideas, but because they’re less blinded and blinkered by their own power. And for that reason, they’re often less hypocritical. And they may have some pragmatic suggestions for us to heed.

Doing this interview for Plough, a Christian magazine, it makes sense to look toward the weaker actors in a system. If “the last shall be first,” that doesn’t simply mean you look to weaker actors with charity, but as possible leaders.

Well, it’s always “the least of these” who deserve priority. Often Christians focus on needing to help them, and rightly so, and we still do need to help a lot of people in the Global South. But the weak are not above action themselves, and they often are less blinded by ambition, pride, and vanity, and that’s a Christian lesson that I have appreciated.