Despite work by think tanks and a few scholars, most often about a particular country’s foreign policy, international relations is hardly a topic for polite classical-liberal conversation. For the past century or so, classical liberals have been rather complacent about this issue, for the most part limiting their statements to the maxim that if only free trade and globalization were increased, the world would become harmonious and peaceful. It may be seriously doubted whether this position ever made much practical sense, but it certainly no longer suffices as a statement of general principles. Global events have an ever-expanding influence on people’s lives, which requires classical liberals to develop comprehensive views on international relations. We are lucky that, from David Hume and Adam Smith onward, many of the great classical-liberal forefathers put forward sophisticated views on this subject. These old ideas have been forgotten or neglected, perhaps owing to academic specialization that has led economists to focus on the economic ideas in the classical-liberal canon (for example, in the works of Smith, Ludwig von Mises, and F. A. Hayek), philosophers on the ideas of Hume, and political theorists on the domestic side of classical-liberal political thought. One result is that classical-liberal thinking is for the most part absent from academic international relations, even though the classical-liberal ideas put forward on this subject still have value for current debates.

Another consequence of the lack of a “standard” classical-liberal view on international affairs is that false ideas about world politics have continued to circulate for many decades, if not centuries. In this article, I focus on a part of the heritage of nineteenth-century liberal thought. From Richard Cobden (1878, 1–21) onward, one element of international relations has had an especially bad press among classical liberals: the balance of power between states, which has been seen as a major cause of war and destruction. As I discuss, this view undeniably contains some truth. Yet the positive effects of the balance of power, in particular its capacity to stabilize international order and therefore to prevent war and misery, have been overlooked completely. Without international order, individual liberty is impossible. This fact alone requires classical liberals to pay more attention to the international balance of power than they have done in the past century and a half.

This oversight seems even more peculiar if one scrutinizes the thought of Friedrich Hayek and his intellectual forebears, such as Hume and Smith. A major element in Hayekian thought is the idea of spontaneous order, in which order emerges unintentionally. I argue that the international balance of power has all the characteristics of Hayekian spontaneous order. This link between Hayek’s ideas and the balance of power is less surprising than it might seem because the great classical-liberal thinkers, such as Hume, Smith, Mises, and Hayek, were rather power oriented in their views on international affairs. Hence, in this article, I call on classical liberals to reappraise the international balance of power, perhaps as part of a general reconsideration of their ideas about international relations.