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What do Classical Liberals have to say about International Politics?

Brian A. Smith

Edwin Van de Haar, Human Nature and World Affairs: An Introduction to Classical Liberalism and International Relations Theory (London: IEA, 2023)

Over the last several years, great power politics returned in earnest. After an apparent vacation from history, the need for politicians to develop good judgment about these matters is as important now as it was during the Cold War.

To whom should they turn for wisdom to deal with threats? Academic historians increasingly disdain diplomatic and military history. Philosophy and theology can offer some moral guidance. But these fields produce little that can help statesmen choose the lesser evil among many.

Political scientists focused on international relations might claim some expertise. After all, their subfield aims at helping us understand trade, war, diplomacy, and other aspects of our world’s politics. The trouble is that rather than developing arguments that aim to inform political judgment, international relations scholars yearn to craft general theories that fit within the discipline’s major research traditions. Proponents of realism tend to look to the structure of the international system and explain state conduct through various conceptions of national interest. Liberalism’s cheerleaders variously predict that democracy, trade, or international institutions will foster peace. To an outsider, these approaches might seem peculiar in that their practitioners seldom appeal to any explicit political worldview. Apart from theories rooted in psychology, such as the realism of Hans Morgenthau, nearly all disdain also any attempt to root their explanations in human nature.

To the degree that any implicit political theory dominates international relations, it is the kind of progressive liberalism to which most scholars personally adhere. So even while realists decry the idea that nation states will ever progress beyond the pursuit of their own interests, most assume that states can rationally understand and exercise control over their populations. The same belief in state competence and knowledge that leads progressives to endorse intensive welfare arrangements is often shared by international relations realists. So-called international liberals might disavow the ability of nation-states to meet the challenges of our day. But they place a great deal of faith in international law and global governance regimes that are supposed to wield collectively the powers that states are individually unable to exercise.

In Human Nature & World Affairs, Edwin van de Haar contends that classical liberalism has been unjustly neglected as an approach to thinking about international politics. Part of the challenge, he notes, is that so few of the great classical liberal writers or statesmen are well-known for their insights into questions of war and peace. Despite the fact these sources exist, they are under-utilized by scholars, a puzzle for which Van de Haar proffers an institutional explanation.

As a discipline, international relations aims at being a predictive science and disdains the approaches that political theorists use to help generate insight into politics and human nature. Classical liberalism’s insights have mostly been developed and applied by political philosophers, social theorists, and economists—only a handful of whom have branched into disciplinary international relations scholarship.

But the problem goes deeper than this. International relations scholars avoid systematic engagement with political philosophy, van de Haar notes, and in general, they profoundly disagree with the worldview classical liberalism suggests. In his book, van de Haar offers a corrective, focusing on the benefits of a viewpoint that can inform political judgment.

Classical liberalism aids this endeavor because it helps us see strong continuities between the ideas we use to grapple with domestic politics and economics, and those we would use to comprehend the global stage. This begins with “a realistic view of human nature,” and one that “values the social nature of individuals but also recognizes their propensity to quarrel, fight and use violence”. Tensions across borders and throughout the globe follow from this premise: “There is no harmony of interests in world politics. States will be able to form an international society, but they will also always face a security dilemma”. Human Nature & World Affairs offers brief introductions to four key thinkers—Hume, Smith, Mises, and Hayek—but van de Haar blends insights from all of them to point readers to a liberty-friendly approach to international politics.

From Hume, van de Haar develops a distinctive account of how we ought to understand the role of human nature in international politics: “All plans depending on a change in human nature were doomed to failure because they were plainly imaginary.” Human beings are not clay waiting to be molded by experts or great leaders. Hume took as a given that national or local pride would dominate affections for other peoples, but this focused sympathy did not rule out trade and diplomacy—and helped stave off anarchy. Hume’s view rested on recognizing the priority of domestic over international obligations. In practice, van de Haar argues that classical liberalism would lead nations to emphasize long-standing treaty obligations and more proximate geographic concerns over a commitment to forms of international humanitarianism or a responsibility to protect far-away peoples.

In Smith, van de Haar finds an even stronger view that psychology explains much about why people focus their moral attention on their countrymen over those more distant. To Smith, “it was natural for humans to put family, friends and the nation first, and also in that order.” Indeed, he argues that this affection imposes a positive duty “to put relatives, friends and country first, in that particular order.” Smith took a less systematic view of international questions, addressing them topically throughout his work, but still showed great insight. To take one example, Smith devoted considerable space in The Wealth of Nations to the argument that successful militaries would rely on professionals to fill their ranks, and speculated on how this might change the nature of war.

Both Mises and Hayek’s writings were deeply informed by the World Wars of the 20th century and confound the typical caricature of the two as “neoliberal globalists.” Each had important arguments focused on the excesses of political power without denying the centrality of nations to human life. Together, they inform a classical liberal view of world politics. Mises believed “the essence of nationality was language, although he acknowledged other characteristics such as geography. He saw a common language as binding the nation but rejected the idea of ‘national character.’” Hayek appears as the “most hawkish” of the thinkers van de Haar studies here: “He did not regard war as a regular policy instrument but saw it as an inevitable feature of life, arising from human nature. His bottom line was that there could be no liberty without safety, therefore international order was of the utmost importance” This focus on order informed Hayek’s opposition to purely open immigration schemes: “He feared the destabilising effects of a large influx of immigrants in a short space of time when entering a relatively homogenous territory.” Critics tend to forget the degree to which both Hayek and Mises began their theorizing from the point of view of the nation-state. This leads them to erroneous conclusions, and to vastly overstate their attachment to globalist projects at the expense of particular polities.

The most valuable sections of the book come later, in several brief chapters where van de Haar develops classical liberalism’s key insights. He implies that such a view is morally realistic in a way that international realists are not. Classical liberalism accepts the authority of history. War has always been with us, an inevitable result of our nature as social but flawed creatures This does not mean that war is a normal instrument of policy to be deployed without regard for morality. Classical liberals tend to embrace the just war tradition’s limits on violence. Classical liberals also reject the realist’s premise of international anarchy. Although there is not and cannot be a world government, states still live together in a relatively structured way that addresses their security needs and allows them to avoid war in many situations.

Unlike international liberals, who tend to be skeptics of nation-states and utterly ignore the knowledge problem, classical liberals accept the wisdom of tacit knowledge and spontaneous orders—many of which appear in international life. Associational and adversarial balances of power are one version, as states work in concert both to build new relationships and react to threats. But classical liberals are also much more likely than other liberals to worry that international law subverts domestic politics. As Samuel Gregg has recently written for FUSION, moreover, they are often skeptical of the view that trade directly fosters peace.

Perhaps most importantly, van de Haar observes that the classical liberal tradition is more serious about the full costs of war than most alternatives. These costs are not simply the obvious losses of blood and national wealth, but include “rules and legislation, often illiberal, that are put into place by the state in response to the threats of war and to enhance the nation’s chances of victory.” As Robert Higgs showed in Crisis and Leviathan, emergencies grow state power, and they rarely cede new areas of authority back to the people. So too do classical liberals grasp the unintended consequences of military intervention and the tremendous challenges inherent in “nation-building.”

Van de Haar offers some cautionary notes to both libertarians and conservatives along the way. He criticizes libertarian approaches to foreign policy as overly economistic, tending to directly import market assumptions into the international scene, and containing utopian propensities like those of progressive liberalism. While this brief criticism hits that mark, he makes too few distinctions among the varied kinds of foreign policy conservatism in play today. Van de Haar does not explain how neoconservatism, national conservatism, free marketers who embrace strategic restraint, or many others fit alongside classical liberal ideals. Yet, in such a brief book, it would be challenging for him to have done so.

The book does suggest that conservatives in the Burkean, Tocquevillean, or Kirkian traditions expect too little progress and too little of human reason. Here, he does not fully succeed in proving the case that most traditionally conservative and classical liberal attitudes differ greatly. One more substantive possibility he does not consider is that classical liberals need conservative views to help reinforce their sense of why order and historical precedents matter. This might have offered a more fruitful approach to the comparison. But this is a minor complaint.

Human Nature & World Affairs is only an introduction. Yet, the book offers an excellent starting point for rethinking foreign policy in a way that emphasizes how much order matters, that remembers protection of life and property remain the core roles of the state, and that fully grasps the terrible cost of war.

Brian A. Smith is editor of Law & Liberty.

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