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Liberalism, between War and Peace
An Interview with Michael Doyle, Part 1

by Marieke Louis , 3 September 2018

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Should democratic states go to war? The first part of this interview with Michael Doyle is devoted to the definition of different intellectual traditions of liberalism, in particular Kant and Mill, in an attempt to examine the necessary conditions of democratic peace.

Michael Doyle is a University Professor of Columbia University in New York, teaching international relations in the Political Science Department, the School of International and Public Affairs and the Law School. His research interests include international relations theory, international law, and international history, and more particularly international peace-building and the United Nations. He is a renowned scholar of liberalism and the theory of democratic peace and just war. He formerly taught at Princeton University, Johns Hopkins University, and the University of Warwick in the United Kingdom. From 2001 to 2003, he served as Assistant Secretary-General and Special Adviser to United Nations Secretary-General Kofi Annan. His responsibilities in the Secretary-General’s Executive Office included strategic planning (the “Millennium Development Goals”), outreach to the international corporate sector (the “Global Compact“), and relations with Washington.

The publications mentioned in this essay are the following:
 Ways of War and Peace: Realism, Liberalism, and Socialism, W.W. Norton, 1997.
 Striking First: Preemption and Prevention of International Conflict, Princeton University Press, 2008.
 Liberal Peace: Selected Essays, Routledge, 2012.
 The Question of Intervention: John Stuart Mill and the Responsibility to Protect, Yale University Press, 2015.

First part: What is a liberal state?

Books & Ideas: Liberalism is a central and recurring topic of your research on war and peace. Liberal thinkers like Kant claim that liberal states are more peaceful than others. How do they support this claim and in which historical and political contexts is it grounded?

M. D.: Liberalism is something that I have been fascinated with ever since the 1980s. It’s deeply part of the overall American culture, but I became interested in it more as a theory and a philosophy. The key idea that liberal states are different contrasts with our dominant mode of thinking in the United States which is international Realism. The Realists say that all states are the functionally the same, caught in anarchy, a “state of war” and driven to balance power. Liberals say that states can be essentially different, that liberal states can bind themselves together in peace and do not need to balance against each other.

Both schools of thought are complex and diverse. When you look at Realists you can find everyone from Thucydides through Machiavelli to Hobbes and Rousseau, among the classics. Then the modern Realists, such as Carr, Morgenthau, Aron and Waltz. On the liberal side as well, there are also different significant strains: from Lockean individualism to Smithian market-based pacifism to Kantian internationalism, which is the most interesting to me and the more complicated. There is not “one” liberalism: liberal theorists agree on human rights and representative government and that liberal states are thus different but then they disagree about what makes them different.

Liberalism is a complex intellectual world. There is no single absolute overriding characteristic of Liberalism: it’s a camp with many different inhabitants attached to it. To give you an example: there are a number of Liberals who think that liberal states are inherently peaceful. One of the most striking is the economist Joseph Schumpeter, who argued in its Sociology of Imperialisms (1919) that democratic-market societies would be inherently peaceful simply because all of the resources that a society needs can be achieved through exchange, and war is inefficient, costly and harmful. Schumpeter is reacting to Marxist-Leninist charges about the inherent aggression of capitalism. As an economist who is committed to the market, he’s very interested in liberating capitalism from the charge of imperialism. And that’s also not unrelated to the kind of views of the “end of history” of Francis Fukuyama advocated at the end of the Cold War, saying that consumerism and democracy make states inherently peaceful. This is part of the liberal tradition but to me that is not very persuasive because it doesn’t fit the historical record of actually existing liberal states.

Kant on the other hand helps us understand the way a liberal state actually does behave. He says that liberal states are not generally peaceful, although they are reluctant to engage in war. Their most striking feature is that they should be, can be and are peaceful towards each other. They establish a separate peace. It doesn’t mean that they don’t engage in wars. If they are surrounded by non-liberal states there could be many wars. Some of those wars are defensive, if they are attacked or even merely threatened by non-liberal states. But as importantly, within liberal states there are pressures that could lead to war: commercial wars to protect property and ideological wars. And these are actions Kant condemns ethically, saying that they are wrong and imprudent, but he understands that they are wrapped up in the character of commercial states. And we do see these patterns in the foreign relations of liberal states.

Most importantly, liberal states have been quite successful in constructing a peace amongst themselves, and it goes back for at least a couple of centuries. But they also have been very active imperialists. While the United States, France, Canada or Great Britain are at peace with each other, it doesn’t preclude them going to war with others, sometimes very imprudently such as the way the US went in Iraq in 2003.

The key to the Kantian version of Liberalism is a peace among liberal states but not necessarily a peace between liberal states and non-liberal states. It’s a separate peace. Not a general pacification.

Kant wrote his Perpetual Peace in 1795. At that time, the closest to liberal states were the Swiss cantons and the French Revolution of 1789. Kant is reacting to the revolution of 1789 and the emergence of popular sovereignty and the doctrine of the “rights of man.” He and many intellectuals saw this as a progressive development. As he was writing, France was in the process of going through the years of Terror, but he doesn’t take that into account: he’s assuming that this aberration will soon stop. And this is before the Thermidorian reaction, and the Napoleonian era. Kant looks at revolutionary republican France as a symbol of hope of a free government, and when he looks at his fellow intellectuals, their feelings of solidarity toward republican France opened for him the possibility of a stable peace among fellow republics. His intellectual context is in reaction to reading and seeking to answer Rousseau’s Social Contract (1762). Rousseau was also aware of the need to explain how a just social contract and a just republic would survive in a world of other States. Rousseau promised that he would write the second volume of the Social Contract, explaining the relationship between Rousseauian democracy and peace. He never did. He did write very interesting essays on Corsica and Poland, and the critique of the Abbé de Saint Pierre was a statement in that direction, but he never produced his answer to how a small democratic republic could establish security and peace without being crushed by its neighbors. Kant reads the Social Contract, and finds it to be the most profound political philosophy he’s ever read; but then he wonders: how do you get peace? Rousseauian social contracts and democracies need to be small, highly participative, communally autonomous republics. How are they not going to be crushed by the states around them? And how would they relate to each other?

Kant argues that, if we thought of republics in a different way - if we had a real republic based on the separation of powers, the idea of freedom - we could solve the problem of peace by their republican self restraint and respect for the autonomy of other states that reflected the autonomy of the citizens that controlled them. These are the premises of the Perpetual Peace and the three conditions of a republican peace: states have to be republican, they have to sign a peace treaty and they have to create a cosmopolitan order that allows contacts across borders. He thought that world would allow you to be free in the domestic sphere, respect cosmopolitan rights and be at peace with other republics. He thought Rousseau did only half the work creating a democratic republic and he never solved the problem of peace. Kant thought that he could do both.

Books & Ideas: Do you see this plurality of views as a strength or a weakness of this school of thought and how do you reconcile these views in your own account of liberal peace?

M. D.: In terms of theory, it’s true that Liberalism is more complex than the simplest version of Realism of Hobbes, John Mearsheimer, or Kenneth Waltz. The structural Realists assume not only that all States are the same but that they are structurally conditioned to be rational actors and have unitary preferences, with security at the top. That’s a very simple market model. The problem is: it is also unrealistic. There has been no successful social science formulation of it that is fully testable, historically speaking. In most cases, states don’t simply balance power against power. If it was so, Canada would have to be an enemy of the US; and Germany and the UK today, an enemy of France. To have a plausible version of realism you have to make it much more historical, descriptive and pluralistic. The way Thucydides or Raymond Aron or many other contemporary realists did and do. This doesn’t bother Waltz; he argues that theory’s job is to simplify and find the essence. I think they leave too much out of international history.

Liberalism is more complicated; although I tried to provide an accessible account of it in the American Political Science Review in 1986. [1] In the modernized model of the Kantian peace you need to have liberal democratic structures, you need to have a public commitment peace with fellow republics and you need transnational relations, including commerce and other ties among countries. All three are needed in order to have a plausible argument for why liberal states are at peace with each other and why they might not be at peace with non-republics. The benefit of it is that you can explain some regular trends toward peace amongst liberal states in world politics over 200 hundred years.

I attempted to provide a map (a catalogue) in my book on War and Peace (1997). What I did was sort out the similarities and differences among Locke, Smith, Schumpeter and Kant. I then tried to illustrate what we could get from each of these theorists and what were their implications for world politics. I found that the most powerful version of liberalism is Kant: he’s the one who explains the most, the best, of the actual behavior of liberal states.

Books & Ideas: According to the liberal theory, which states could be described as “liberal” states in the current period?

M. D.: It’s an important exercise because in order for a theory to be tested you have to have it tested against empirical knowledge, both large scale patterns and individual case studies. This means you have to code ideas that are at their heart philosophical into empirical analogues, indicators, that you can then systematically examine. There is an element of judgment. If you take a very narrow read of liberalism, you will find that liberal states (the very few of them!) behave beautifully because you have created such a high standard to which only Sweden qualifies. On the other hand, if you take a standard that is so broad, then you’re not identifying what’s special about the liberal states.

There is an element of judgment in that exercise and the best thing you can do is be very transparent. I extract from Kant an understanding of what a liberal state is, and from that I develop four modern criteria: First, there needs to be a cultural recognition of equal human dignity. Second you need a private property economy: it doesn’t mean Thatcher or Reagan neoliberalism, but there has to be a degree of private ownership of houses and some businesses. You can certainly have mixed economies and social democracies as in Sweden or elsewhere. Third the State has to be sovereign: it can’t be part of another state or a colony. It has to be an independent state. Lastly it has to be democratic and representative. For Kant for instance, the separation of powers is very important too. There need to be institutions where people have a determining voice in setting the broadest dimensions of public policies, including foreign and defense policies at least indirectly through budgetary control. All these elements need to be coded. I did that in 1983 coding States from the 18th century to the present time where the data sources are more reliable. The idea was to have a broad conception of what a liberal republic would be in order to test the Kantian propositions in a demanding way.

In the present world, many of the States that we call regular democracies qualify as liberal states. Great Britain, France, the United States, Canada, Australia, Japan and many more. For a brief period of time in the 1990s when Russia was under Boris Yeltsin it was going in that direction but not during the Putin era where there are no free and fair elections. China has never (not yet?) been a liberal state.

Books and Ideas: What difference do you make between a liberal and a democratic state?

M. D.: There is a large amount of overlap between what we call consolidated democracies and liberal states. Today it’s pretty much the same thing, but not in the past. There were states that we could categorize as liberal that we would not call democratic. For instance, we would categorize the US after the Civil War as a liberal state but it wasn’t democratic in the sense that women didn’t vote. In France, I date 1830 to 1848 as liberal, I date 1790 to 1793 as also liberal during the First Republic and then again after 1870 but women couldn’t vote, so it’s not democratic. Reciprocally, a democratic state might not be liberal. Analytically, if we take a narrow reading of democracy based on majority rule we have a possibility of majoritarian tyranny. What about a democracy that is committed to racist understandings of itself or that is not committed to the protection of minority rights, or that is communist totalitarian? It wouldn’t be a liberal state. Again, to emphasize: I draw the lines with a bias toward inclusiveness in order to encompass both liberal and quasi-liberal states in order to better test the propositions. The fact that Sweden doesn’t go to war with Norway anymore is great, but it doesn’t test the proposition of a broader understanding on liberalism.

Books & Ideas: In your last book The Question of Intervention, you focus on the thought of John Stuart Mill and his doctrine of non-intervention in 1859, considering its implication for the post-1990s era. Why did you decide to engage in this dialogue with Mill?

M. D.: The first reason why I turned to Mill is because the first thing I was assigned in my first academic course in international relations on the topic of intervention was Mill’s essay on “Non-Intervention.” Most international relations students, as I did when I was 18 years old, would read Mill’s essay as the classic statement on intervention. The second reason is that having written on liberalism, for me the question of intervention is very important. When one should intervene is a vitally important question because what gives liberal states their essential legitimacy is their self-determination— an individual’s availability to decide his or her own fate in the political realm. So the dilemma is: how can one polity intervene justly in another if the source of everyone’s political life and legitimacy should be domestic self-determination?

Mill’s answer is: “Don’t intervene”. This is why the essay is “Non-Intervention.” But he then proceeds to raise numerous exceptions. This is an essential question for Liberals: If you’re Hobbesian you intervene whenever it’s advantageous: if it adds to your power, your wealth or your prestige. For Liberals it’s a moral and political problem. The third reason I dealt with Mill is because he’s often misinterpreted. The Essay is often read as a way to assert that you can’t intervene in the “civilized” world but that you can in the colonies - a “non-civilized” world. This is the neo-colonial interpretation of Mill. But that view is oversimplified: he does justify imperialism by advancing reasons for it (which are not very good) and I criticize them. But he also does argue for intervention in the civilized world, justifying it when it helps free people from foreign rule, as in Belgium in 1830, or stops a massacre or a civil war as took place in Portugal. And the reasons for intervention in the civilized world are not unrelated to the excuses he offers for intervention in the colonial world.

Books & Ideas: Generally speaking, do you think that a better understanding of international politics starts with returning to the classics of political theory?

M. D.: I’ve often gone back to classical theorists. The simplest reason is that when I was a student, we all had to be political theorists. As a graduate student it was a required field. We all had to demonstrate that we knew the classics of political theory, Ancients and Moderns, in order to get our PhD. Political theory was part of our education back in those days, it’s not the case anymore in our graduate programs. That’s only a personal reason. The substantive reason is that the classics articulate the fundamental problems of international politics in ways that many modern writers do not. For example, I am a great admirer of Kenneth Waltz (1924-2013). To understand the questions that are fundamental to Realism, you’ve got to read Hobbes and Rousseau. Hobbes and Rousseau answer those tougher questions: what kind of a state can be assumed to be a unitary actor? Why should we accept as legitimate a state that is a unitary actor? Going to the classics allows you to go deeper. Later contemporary Realists tend to neglect the basic assumptions that make their theory work, or not. When you want to go to even more complex questions like the origins of war, you can’t do better than Thucydides. His virtue is to bring together so many factors at the same time and yet have them cohere. Few modern scholars succeed in this. I haven’t always begun with the classics. But it’s correct that I have often tried to understand fundamental questions by going back to the classics. Yet, I am not an anti-positivist: what I do, sometimes to the frustration of my friends in political theory, is extract testable propositions from political theorists as I did with Kant and Mill.

by Marieke Louis, 3 September 2018

To quote this article :

Marieke Louis, « Liberalism, between War and Peace. An Interview with Michael Doyle, Part 1 », Books and Ideas , 3 September 2018. ISSN : 2105-3030. URL :

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[1Liberalism and World Politics”, APSR, 80 (4), 1986

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