In a recent article in the journal International Security, I offered an explanation for a puzzling aspect of democratic America's post–Cold War foreign policy: its increasingly expansive and interventionist cast.Footnote ¹ Building upon Louis Hartz's famous argument about how America's “liberal tradition” could paradoxically produce domestic illiberalism, I sought to explain recent manifestations of America's international illiberalism, such as the drive for hegemony and the willingness to intervene in various countries to remake the world in its own liberal political (democracy) and economic (free markets) image, as also rooted in American liberalism.Footnote ²

The idea that liberalism, imperialism, and other forms of international illiberalism are not only compatible, but perhaps inextricably linked, has gained currency among many scholars. As Uday Singh Mehta puts it in his study of the intellectual underpinnings of the British Empire: “it is liberal thinkers … who, notwithstanding—indeed, on account of—their reforming schemes, endorse the empire as a legitimate form of political and commercial governance; who justify and accept its undemocratic and nonrepresentative structure; who invoke as politically relevant categories such as history, ethnicity, civilizational hierarchies, and occasional race and blood ties; and who fashion arguments for the empires’ at least temporary necessity and foreseeable prolongation.”Footnote ³ Mehta's book is part of a burgeoning literature exploring the many compatibilities between liberal thinkers such as Jeremy Bentham, James Mill, John Stuart Mill, Thomas Babington Macaulay, Alexis de Tocqueville, and John Locke and their countries’ imperial projects. The root of this compatibility between liberalism and empire is what David Hume called its “imprudent vehemence” in dealing with nonliberal actors.Footnote ⁴

One of the places where I parted company from Hartz was in my assessment of where the philosophical roots of this paradox of liberalism lay.Footnote ⁵ For him, the wellspring of America's illiberalism was to be found in Locke's liberalism. American Lockeanism, in Hartz's view, developed universal pretensions because of its ignorance of the major alternatives to it on the Left (socialism) and the Right (feudalism).Footnote ⁶ This leads American liberalism to simultaneously overstate the threats it faces by identifying the nonliberal with the enemy and underestimate the difficulties it would face, from both foes and friends, in remaking the world in its liberal image. In my view, Hartz erred both in his interpretation of Locke and also in trying to use “irrational Lockianism” to explain American foreign policy given how little Locke said about international relations. Rather, I argued that if we want to understand the core dynamics of the liberal approach to world politics, we need to go to its philosophical fountainhead.Footnote ⁷ In “America's Illiberal Liberalism,” I sought to highlight the compatibilities between liberalism and imperialism in the thought of perhaps the greatest liberal thinker of international relations: Immanuel Kant.

I began with the observation that of the liberal social-contract theorists, Kant has by far the most pessimistic view of life in the international state of nature. This might strike some readers as counterintuitive inasmuch as most international relations scholars associate the notion of the international state of nature as a “state of warre” with Thomas Hobbes. But Hobbes simply used the anarchical relations among sovereigns in the international system as a metaphor to illustrate what life was like for individuals before the establishment of the commonwealth. He hastened to qualify this analogy by remarking that “there does not follow from it that misery which accompanies the liberty of particular men,” because states, unlike individuals, are much less susceptible to death.Footnote ⁸

It was, in fact, Kant who argued that the international state of nature is also quite perilous for states.Footnote ⁹ As he puts it in The Philosophy of Law, “this natural condition is a state of war in which the Right of the stronger prevails; and although it may not in fact be always found as a state of actual war and incessant hostility, and although no real wrong is done to any one therein, yet the condition is wrong in itself in the highest degree, and the Nations which form States contiguous to each other are bound mutually to pass out of it.”Footnote ¹⁰ In consequence, it is therefore imperative, both practically and morally, to establish a state of international “lawfulness.”

One key to making states lawful is that the nature of their domestic regimes be broadly representative. It is only when a state has republican political institutions that other states can be sure that it will respect the rights of other states in the international system. As Kant put it, “if the form of government is to cohere with the concept of right, it must include the representative system, which is possible only in a republican form of government and without which (no matter what the constitution may be) government is despotic and brutish.”Footnote ¹¹

In the text of his famous essay Perpetual Peace, Kant argues that this “state of peace” must be “established” among neighbors, and in a note to that text, he explains that a state which is “merely in a state of nature denies me this security and injures me merely by being in this state.”Footnote ¹² But given that Kant's “Fifth Preliminary Article for Perpetual Peace Among Nations” holds that “no nation shall forcibly interfere with the constitution and government of another,” the question becomes: What recourse do “lawful” (i.e., republican) states have in dealing with these other states?

My solution is to follow Kant in distinguishing between “just” and “unjust enemies,” the latter of which he defines as those “whose publically expressed Will, whether in word or deed, betrays a maxim which, if it were taken as a universal rule, would make a state of Peace among nations impossible, and would necessarily perpetuate the state of Nature.”Footnote ¹³ Against such enemies, Kant avers, “the Right of a State … has no limits.”Footnote ¹⁴

In sum, the state of nature is so dangerous for Kant that it must be superseded. The only way to end the international state of nature once and for all is for all states to embrace representative political regimes. And so, those states that refuse to do so represent a threat to other states merely by virtue of their domestic regimes. Hence, liberal interventionism is defensible both practically and morally by this reading of Kant.

James Lindley Wilson and Jonathan Monten present a nuanced and thoughtful critique of my argument about the Kantian roots of the phenomenon of “liberal imperialism.” Of course, Kant is a notoriously complex, abstruse, and even contradictory thinker and so it is not surprising that my interpretation would raise some objections. To quote prominent Kant scholar Carl Joachim Friedrich, “it would be rash to assume that where so many have found such divergent emphases there is likely to be agreement upon the interpretation here set forth.”Footnote ¹⁵

Specifically, Wilson and Monten make two related points: First, they posit that, properly understood, Kant's writings, particularly but not exclusively Perpetual Peace, present a brief for nonintervention. Second, and following from that interpretation, they conclude that the problem today with the United States is not that its “liberal tradition” is leading it to international illiberalism, but rather that it is insufficiently faithful to the liberal tradition that would, in fact, lead it to eschew international intervention. I make five points in response.

To begin with, Wilson and Monten suggest that my interpretation of Kant is out of step with the literature and they challenge my use of some of these sources. In particular, they read Thomas Pangle and Peter Ahrensdorf and Pierre Hassner differently than I do on Kant. But as I will show through extensive quotation, both these sources fully support my points about Kant's willingness to accept the use of force to end the state of nature and the fundamental problems with the practical application of Kant's system in the real world.

On the former, as Pangle and Ahrensdorf directly state, “Kant repeatedly affirms [that] coercion can and should be used to compel one's neighbors to enter into the international social contract, just as coercion is justified to end the state of nature among individuals (for this coercion does not compel morality but only external behavior that will end the threat to national and hence personal security).”Footnote ¹⁶ The only interesting question is when and under what conditions such coercion can be applied. My answer is that it is when it is used by republican states against nonrepublican states to force them out of the state of nature.

On the latter, they assume—and this is a second problem with their argument—that Kant presents a clear and workable liberal framework for ending the international state of nature without the use of coercion and force. But as Pierre Hassner suggests, Kant does not, in fact, present a practical political program:

Given these inconsistencies in Kant, his philosophy hardly constitutes an alternative basis upon which to constitute a liberalism not prone to empire and intervention.

A third problem is that Wilson and Monten conflate two distinct arguments in Kant. There is no doubt that they are correct that Kant eschewed a plan for perpetual peace based upon a coercive world state that decreed peace by diktat and enforced it with blood and iron. What Kant had in mind, clearly, was a system of independent states that willingly choose to live in peace with each other.Footnote ¹⁸ But the key to such a system, in Kant's view, was that they be organized internally in a republican fashion. For this freely operating system to work, absent an overarching global sovereign, the domestic regimes of the constituent states all had to be republican. Intervention to spread republican regimes, then, is not necessarily part and parcel of the world state; indeed, it could serve as the means to avoid it.

A fourth problem with Wilson and Monten's argument is that it does nothing to address and reconcile the unresolved tension in Kant between his Fifth Preliminary Article (“No nation shall forcibly interfere with the constitution and government of another”) and the First Definitive Article (“The civil constitution of every nation should be republican”).Footnote ¹⁹ Indeed, they sidestep it by admitting that Kant is complex and then emphasizing his noninterventionist elements.Footnote ²⁰ In contrast, my argument squarely addresses this tension by giving priority to the “definitive” over the “preliminary” articles, and then showing how intervention can be justified as an exception to the latter within the Kantian framework by virtue of the fact that Kant defines “unjust enemies” as those who refuse to leave the state of nature and therefore forfeit the rights and protections of sovereignty. Indeed, in The Philosophy of Law, Kant even offers a rationale for preventive war: “A less powerful country may be involved merely in the condition of a more powerful neighbor prior to any action at all; and in the State of Nature an attack under such circumstances would be warrantable. This international relation is the foundation of the Right of Equilibrium, or of ‘balance of Power,’ among all States that are in active contiguity to each other.”Footnote ²¹

It is important to distinguish between the different types of intervention. There is, of course, self-interested intervention to advance a state's particular interests, which Kant clearly eschews. Jennifer Pitts, another important scholar of liberal imperialism, emphasizes Kant's opposition to this sort of “autocratic imperialism.”Footnote ²² But there are also defensive and altruistic rationales for intervention. It is not at all clear that they are incompatible with Kant's categorical imperative: “Act only on that maxim through which you can at the same time will that it should become a universal law.”Footnote ²³ After all, who better than a republican state, acting defensively and with the best interests of the rest of world at heart, to constitute the just exception?

The final problem is that Wilson and Monten do not engage the most serious challenge to my interpretation of Kantian liberal imperialism: not that it is prohibited under all circumstances (as they argue), but rather that it is actually unnecessary in Kant's framework. Kenneth Waltz, for example, characterizes Kant as a “noninterventionist liberal” on the grounds that “nature,” rather than liberal states, operating secretly through war and power politics, brings about perpetual peace without the conscious actions of states. It does so, in Kant's words, through “the desire of every nation (or its ruler) … to dominate the entire world” which instead produces “an equilibrium of the liveliest competing powers.”Footnote ²⁴ Waltz at least resolves the tension between the Fifth Preliminary and the First Definitive Articles by having nature do the dirty work of establishing perpetual peace through “its hidden plan” to drive states voluntarily to embrace domestic and international republicanism.

However, Waltz's argument, even if it is correct, does little to bolster Wilson and Monten's claim that a purer Kantian liberalism would make the world less conflictual, at least in the short run, inasmuch as the driving force in Waltz's view of Kant is the invisible hand of nature, rather than self-consciously liberal states themselves. Such an argument seems far removed from most other arguments that focus on the putative pacifying effects of liberalism on state behavior. Without stalemate as the unintended consequence of war among states, states have little incentive to end the international state of nature and voluntarily embrace the Republican League. Waltz's argument, of course, takes us back in the direction of realism that Wilson and Monten sought to steer us away from in the first place, albeit the defensive version Waltz advances in his Theory of International Politics.

In sum, there is a growing consensus that liberalism and aggressive international behavior not only are compatible, but are in fact causally linked in the thought of many of liberalism's greatest thinkers. To that list, we must now add Immanuel Kant as well. One can find in Kant a categorical prohibition of liberal imperialism only by ignoring Kant's characterization of the state of nature as perilously dire and his definition of the “unjust enemy” as one who would perpetuate it by not embracing republican political forms and against whom any means may be employed.

Even assuming for the sake of argument that Wilson and Monten are correct that despite all of this evidence to the contrary, Kant ultimately ended up where he began, with the Fifth Preliminary Article's unqualified prohibition of intervention, the practical manifestations of Kantianism suggest that that is not where most of his liberal followers end up.Footnote ²⁵ As Woodrow Wilson explained in his April 2, 1917 declaration of the war to end all wars, changing the domestic nature of Imperial Germany was part and parcel of making the world safe for the League of Nations, the closest the world has ever come to seeing Kant's Republican League in action: “We are accepting this challenge of hostile purpose because we know that in such a government, following such methods, we can never have a friend; and in the presence of its organized power, always lying in wait to accomplish we know not what purpose, there can be no assured security for the democratic governments of the world.”Footnote ²⁶

Eighty-six years later, President George W. Bush justified his administration's invasion of Iraq on similar grounds: “A free, democratic, peaceful Iraq will not threaten America or our friends with illegal weapons. A free Iraq will not be a training ground for terrorists, or a funnel of money to terrorists, or provide weapons to terrorists who would be willing to use them to strike our country or allies. A free Iraq will not destabilize the Middle East. A free Iraq can set a hopeful example to the entire region and lead other nations to choose freedom. And as the pursuits of freedom replace hatred and resentment and terror in the Middle East, the American people will be more secure.”Footnote ²⁷ It would be nice if liberal statesmen interpreted Kant the way Wilson and Monten do, but they clearly do not. My point is that Kant is himself to blame: at best he is unclear and at worst he provides a seductive brief on behalf of liberal imperialism.