A Libertarian Theory of War
[The Myth of National Defense (2003)]
The libertarian movement has been chided by William F. Buckley, Jr., for failing to use its "strategic intelligence" in facing the major problems of our time. We have, indeed, been too often prone to "pursue our busy little seminars on whether or not to demunicipalize the garbage collectors" (as Buckley has contemptuously written), while ignoring and failing to apply libertarian theory to the most vital problem of our time: war and peace. There is a sense in which libertarians have been utopian rather than strategic in their thinking, with a tendency to divorce the ideal system which we envisage from the realities of the world in which we live.
In short, too many of us have divorced theory from practice, and have then been content to hold the pure libertarian society as an abstract ideal for some remotely future time, while in the concrete world of today we follow unthinkingly the orthodox "conservative" line. To live liberty, to begin the hard but essential strategic struggle of changing the unsatisfactory world of today in the direction of our ideals, we must realize and demonstrate to the world that libertarian theory can be brought sharply to bear upon all of the world's crucial problems. By coming to grips with these problems, we can demonstrate that libertarianism is not just a beautiful ideal somewhere on cloud nine, but a tough-minded body of truths that enables us to take our stand and to cope with the whole host of issues of our day.
Let us then, by all means, use our strategic intelligence — although, when he sees the result, Mr. Buckley might well wish that we had stayed in the realm of garbage collection. Let us construct a libertarian theory of war and peace.
The fundamental axiom of libertarian theory is that no one may threaten or commit violence ("aggress") against another man's person or property. Violence may be employed only against the man who commits such violence; that is, only defensively against the aggressive violence of another. In short, no violence may be employed against a nonaggressor. Here is the fundamental rule from which can be deduced the entire corpus of libertarian theory.
Let us set aside the more complex problem of the State for a while and consider simply relations between "private" individuals. Jones finds that he or his property is being invaded, aggressed against, by Smith. It is legitimate for Jones, as we have seen, to repel this invasion by defensive violence of his own. But now we come to a more knotty question: Is it within the right of Jones to commit violence against innocent third parties as a corollary to his legitimate defense against Smith? To the libertarian, the answer must be clearly no.
Remember that the rule prohibiting violence against the persons or property of innocent men is absolute: it holds regardless of the subjective motives for the aggression. It is wrong and criminal to violate the property or person of another, even if one is a Robin Hood, or starving, or is doing it to save one's relatives, or is defending oneself against a third man's attack. We may understand and sympathize with the motives in many of these cases and extreme situations. We may later mitigate the guilt if the criminal comes to trial for punishment, but we cannot evade the judgment that this aggression is still a criminal act, and one which the victim has every right to repel, by violence if necessary.
In short, A aggresses against B because C is threatening, or aggressing against, A. We may understand C's "higher" culpability in this whole procedure, but we must still label this aggression as a criminal act which B has the right to repel by violence.
To be more concrete, if Jones finds that his property is being stolen by Smith, he has the right to repel him and try to catch him; but he has no right to repel him by bombing a building and murdering innocent people or to catch him by spraying machine-gun fire into an innocent crowd. If he does this, he is as much (or more of) a criminal aggressor as Smith is.
The application to problems of war and peace is already becoming evident. For while war in the narrower sense is a conflict between States, in the broader sense we may define it as the outbreak of open violence between people or groups of people. If Smith and a group of his henchmen aggress against Jones, and Jones and his bodyguards pursue the Smith gang to their lair, we may cheer Jones on in his endeavor; and we, and others in society interested in repelling aggression, may contribute financially or personally to Jones's cause.
But Jones has no right, any more than does Smith, to aggress against anyone else in the course of his "just war": to steal others' property in order to finance his pursuit, to conscript others into his posse by use of violence, or to kill others in the course of his struggle to capture the Smith forces. If Jones should do any of these things, he becomes a criminal as fully as Smith, and he too becomes subject to whatever sanctions are meted out against criminality.
In fact, if Smith's crime was theft, and Jones should use conscription to catch him or should kill others in the pursuit, Jones becomes more of a criminal than Smith, for such crimes against another person as enslavement and murder are surely far worse than theft. (For while theft injures the extension of another's personality, enslavement injures, and murder obliterates, that personality itself.)
Suppose that Jones, in the course of his "just war" against the ravages of Smith, should kill a few innocent people, and suppose that he should declaim, in defense of this murder, that he was simply acting on the slogan, "Give me liberty or give me death." The absurdity of this "defense" should be evident at once, for the issue is not whether Jones was willing to risk death personally in his defensive struggle against Smith; the issue is whether he was willing to kill other people in pursuit of his legitimate end. For Jones was in truth acting on the completely indefensible slogan: "Give me liberty or give them death" — surely a far less noble battle cry.
The libertarian's basic attitude toward war must then be: It is legitimate to use violence against criminals in defense of one's rights of person and property; it is completely impermissible to violate the rights of other innocent people. War, then, is only proper when the exercise of violence is rigorously limited to the individual criminals. We may judge for ourselves how many wars or conflicts in history have met this criterion.
It has often been maintained, and especially by conservatives, that the development of the horrendous modern weapons of mass murder (nuclear weapons, rockets, germ warfare, etc.) is a difference only of degree rather than kind from the simpler weapons of an earlier era. Of course, one answer to this is that when the degree is the number of human lives, the difference is a very big one. But another answer that the libertarian is particularly equipped to give is that, while the bow and arrow and even the rifle can be pinpointed, if the will be there, against actual criminals, modern nuclear weapons cannot. Here is a crucial difference in kind.
Of course, the bow and arrow could be used for aggressive purposes, but it could also be pinpointed to use only against aggressors. Nuclear weapons, even "conventional" aerial bombs, cannot be. These weapons are ipso facto engines of indiscriminate mass destruction. (The only exception would be the extremely rare case where a mass of people who were all criminals inhabited a vast geographical area.) We must, therefore, conclude that the use of nuclear or similar weapons, or the threat thereof, is a sin and a crime against humanity for which there can be no justification.
This is why the old cliché no longer holds that it is not the arms but the will to use them that is significant in judging matters of war and peace. For it is precisely the characteristic of modern weapons that they cannot be used selectively, cannot be used in a libertarian manner. Therefore, their very existence must be condemned, and nuclear disarmament becomes a good to be pursued for its own sake.
And if we will indeed use our strategic intelligence, we will see that such disarmament is not only a good, but the highest political good that we can pursue in the modern world. For just as murder is a more heinous crime against another man than larceny, so mass murder — indeed, murder so widespread as to threaten human civilization and human survival itself — is the worst crime that any man could possibly commit. And that crime is now imminent. And the forestalling of massive annihilation is far more important, in truth, than the demunicipalization of garbage disposal, as worthwhile as that may be. Or are libertarians going to wax properly indignant about price control or the income tax, and yet shrug their shoulders at, or even positively advocate, the ultimate crime of mass murder?
 There are some libertarians who would go even further and say that no one should employ violence even in defending himself against violence. However, even such Tolstoyans, or "absolutist pacifists," would concede the defender's right to employ defensive violence and would merely urge him not to exercise that right. They, therefore, do not disagree with our proposition. In the same way, a libertarian temperance advocate would not challenge a man's right to drink liquor, only his wisdom in exercising that right.
 We shall not attempt to justify this axiom here: Most libertarians and even conservatives are familiar with the rule and even defend it; the problem is not so much in arriving at the rule as in fearlessly and consistently pursuing its numerous and often astounding implications.
 Or, to bring up another famous antipacifist slogan, the question is not whether "we would be willing to use force to prevent the rape of our sister," but whether, to prevent that rape, we are willing to kill innocent people and perhaps even the sister herself.
 William Buckley and other conservatives have propounded the curious moral doctrine that it is no worse to kill millions than it is to kill one man. The man who does either is, to be sure, a murderer; but surely it makes a huge difference how many people he kills. We may see this by phrasing the problem thus: after a man has already killed one person, does it make a difference whether he stops killing now or goes on a further rampage and kills many dozen more people? Obviously, it does.
Note: The views expressed on Mises.org are not necessarily those of the Mises Institute.