On the Balance of Power in Hume, and especially Kant

One reason why I have a tendency to deny that Hume is a proto-liberal is that he is rather fond of the international balance of power. This is especially clear in his 1752 essay on “The Balance of Power” (but it also shows up in his History). Whereas I want to claim that this contrasts with an embrace of international federalist project as a means toward peace by the first generation of liberals, Adam Smith, Kant, and Bentham.

Until recently, I assumed that Kant was a fierce critic of the balance of power because in order to preserve it one must constantly go to war, or be willing to do so. This is how I read a remark in the third part of his (1793) essay “On the Common Saying: ‘This May be True in Theory, But it does not apply in Practice,” where he writes “For a permanent universal peace by means of a so-called European balance of power" is a pure illusion, like Swift's story of the house which the builder had constructed in such perfect harmony with all the laws of equilibrium that it collapsed as soon as a sparrow alighted on it.” (Kant’s Political Writings, Cambridge University Press, p. 92) I am not alone in reading Kant like this because in the “Introduction” of his Kant’s Political Writings, Heiss claims “Kant harshly attacks the concept of the balance of power because it cannot lead to perpetual peace.” (p. 34)

So, I was a bit surprised to read in an excellent essay by Frederick G. Whelan that “By the end of the [eighteenth century] century no less an anti-Machiavellian moralist than Kant was prepared to advocate a right to maintain the balance of power by force, if necessary,” (Whelan, Frederick G. "Robertson, Hume, and the balance of power." Hume Studies 21.2 (1995): 327. He cites, paragraph 65 from Kant’s (1797) Metaphysics of Morals. This material can also be found in Kant’s Political Writings! I quote:

In the state of nature, the right to make war (i.e. to enter into hostilities) is the permitted means by which one state prosecutes its rights against another. Thus if a state believes that it has been injured by another state, it is entitled to resort to violence, for it cannot in the state of nature gain satisfaction through legal procedings, the only means of settling disputes in a state governed by right. Apart from an actively inflicted injury (the first aggression, as distinct from the first hostilities), a state may be subjected to threats. Such threats may arise either if another state is the first to make military preparations, on which the right of anticipatory attack (ius praeventionis) is based, or simply if there is an alarming increase of power (potentia tremenda) in another state which has acquired new territories. This is an injury to the less powerful state by the mere fact that the other state, even without offering any active offence, is more powerful; and any attack upon it is legitimate in the state of nature. On this is based the right to maintain a balance of power among all states which have active contact with one another.—p. 167 (in Kant’s Political Writings) [emphases in original]

Judging by Whelan’s footnotes (see note 28), I wouldn’t be surprised if Kant is here directly echoing Vattell’s Law of Nations.

It is tempting, of course, to treat Kant’s criticism of balance of power politics as a normative argument and his apparent embrace of it as a reporting of an existing practice while keeping it at arms length. But I don’t think that works because some of Kant’s most ingenious arguments in his (1795) Perpetual Peace, especially, are built on premises committed to Hobbesian state of nature reasoning.

One could argue, of course, that Kant simply changed his mind on the balance of power. And for all I know that’s what happened. It would, of course, ruin my attempt to treat the rejection of balance of power doctrines as a kind of founding constitutive moment of liberalism. (And some of my readers who dislike my tendency toward anachronism will feel vindicated.)

So, I am more inclined to treat Kant’s embrace of the balance of power politics as inaugurating a kind of theory of the second-best (or Nth best) within liberalism. Absent powerful pacific federations that can regulate the commerce and intercourse of all peoples, which is the normatively desirable (first best) state of affairs, the prudential state of nature rules still apply (as a second best).

In fact, the contrast between first-best and second-best strategies should not be overdone in the previous paragraph: at no point does the Kantian liberal demand from states, or in the art of governing them, that they forego elementary prudence. The critique of the balance of power is, in fact, not idealist in character in Kant. It’s just that it is self-defeating and unworkable if you wish to aim for peace. Similarly, it is self-defeating from the point of prudence to ignore the potential threats of growing or would be great powers. In fact, one may well argue that the process toward perpetual peace could only begin in a defensive federation balancing against a would be threatening regional power—all the way signaling that more gains are to be hard from mutual cooperation.