Quick note on proportionality jus ad bellum and the law of belligerent reprisal

(Update, July 28, 2007, Friday. Welcome Instapundit readers and thanks to Glenn for the Instalanche! I had been planning on revising this entry but didn't get around to it. But let me make some revisions now ... I will leave the original post at the bottom of all this. My intent is not to go on and on, but to make a basic point about proportionality and the law of belligerent reprisal. It is not intended to be a technical post, with footnotes and long explanations.

(I have posted a longer, legally technical comment on proportionality in jus in bello, proportionality in the conduct of armed conflict, here, as well as a useful comment by Geoffry Corn, here. I have also reposted an article on the history of the laws of war and the difficulties of asymmetric warfare - ie, warfare where the other party does not respect the combatant/noncombatant distinction - that I wrote for the New York Times Magazine at the opening of the Iraq war in 2003, here. And a group letter, issued at the opening of the Iraq war, noting that defenders in armed conflicts have legal obligations to protect civilians, not just attackers, here. I also have posted a variety of things on Hamdan, Common Article Three, if you poke around. And here is a post on the meta-theory of the just war, comparing Walzer and Catholicism's versions of just war theory. But here are some additional and revising comments on proportionality and jus ad bellum:)

The Lebanon conflict has seen much discussion of the concept of proportionality, as a moral concept in the theory of the just war, and as a legal concept. It applies in two separate contexts - one, the conduct of armed parties in war, jus in bello, which I discuss here and, second, the war aims of parties in making the determination to resort to force, jus ad bellum. I briefly and non-technically address a part of the second, jus ad bellum, issue of proportionality in this post.

As a matter of the moral theory of the just war, proportionality applies to the decision by a party to resort to force. The war aims of a party in resorting to force must be, in a broad moral sense, proportionate to the wrong suffered. I stress broad moral sense, because the harm suffered includes not only actual harms suffered in a particular incident of aggression - a rocket attack upon civilian targets or, for that matter, military ones ; kidnapping for hostages; etc. - but the threat posed by the continuing possibility of such action and their escalation. The determination of the extent of a threat, how great it is, and what it takes to eliminate it are traditionally in the hands of a state. Credible threats of unjust aggression are aggression in the theory of the just war as much as actual action, and for obvious moral reasons.

A sovereign state has an obligation to protect its people against credible threats of unjust aggression; and in traditional just war theory, the leaders of a state have the obligation to decide what constitutes a credible threat and how to respond to it. Note that in the Catholic catechism - I am not a Catholic, and understand its discussions of the just war as a species of casuistical moral theory, not transcendental doctrine - the determination of these matters is not given to theologians, bishops, or religious authorities, but instead to leaders who must weigh up the considerations of the common welfare, including its safety. It is the Christian obligation of those leaders to make those determinations, for which, presumably, they must answer to God; their obligation to the just safety of their people is an obligation of Christian love.

Note, too, that the moral obligation of a state to protect its people does not just apply to just, democratic, or "decent" states; it is a more fundamental obligation of sovereignty than even justice or decency. Saudi Arabia, for example, is neither just nor decent, but its rulers have an obligation to protect its people from exterior attack. There are limitations on this, in the form of not merely unjust or wicked states, but states that are, for example, genocidal - but in general, a state need not be virtuous in order to have the obligation and rights of a sovereign to protect its people from outside aggression.

That said, much of the comment on proportionality in Israel's war aims in the Lebanon conflict has been based around the assumption that it must be proportional to the immediate incidents which sparked retaliation - the kidnapping of Israeli soldiers as hostages and the most immediate rocket attacks upon civilians. As noted above as a matter of moral theory, the response to aggression is not predicated upon the triggering incident, but instead upon the threat presented - the evaluation of which lies in the hands of a state and its leadership. Israel is free, as a matter of just war theory, to determine that it will not suffer rocket attacks upon its civilian population into the future and to determine, as a matter of the prudential considerations of military necessity, that now, rather than later, is the time to remove the threat. That determination is a question of proportionality measured against aggression and threat of aggression, not against any particular triggering incident.

There is a separate question of proportionality, jus in bello, of what conduct in war may be used to pursue a war aim to remove the underlying threat. Does it, for example, include attacks upon infrastructure and mingled civilian and military objects. What difference does it make that the enemy has deliberately commingled civilian and military objects? I have (albeit briefly) dealt with those questions on other posts; the issue here is proportionality in jus ad bellum.

There seems to be some confusion as to two separate legal concepts in what constitutes a proportionate response in jus ad bellum. One is simply the matter of going to war with the intention of removing the threat - which a party might reasonably determine requires surrender by the other side, regime change, or other drastic actions. The requirement of proportionality, as noted, is determined by the nature of the threat.

The second legal concept is that of the law of belligerent reprisal. It is a narrow doctrine, with narrow although important application, in which proportionality plays a special role. There are circumstances, long recognized in customary law of jus ad bellum, in which states will make incursions or aggressions of a limited nature against another party. The underlying reality is that the two states do not want fully to commit to war. But the risk of not responding to an armed provocation can be severe - it invites the other party to see weakness and continue to press with provocations. The law of belligerent reprisal allows a party that has been the subject of an armed provocation to retaliate, in order to make clear to the other party that it will defend its sovereignty, but to do so in a way that sends a legal signal that it will not escalate the conflict if the other party does not. It is a form of legal self-help - responding with force, but force that is proportionate to the immediate provocation and intended to close the circle of violence and cut it off with a single tit-for-tat, rather than see it spiral upwards into full conflict. Reprisal in the law of war is retaliation characterized by the intention to right a wrong or respond in kind to a wrong, but to do so in a way that invites the other party back to the legal status quo ante. The key legal elements that convert retaliation into legal reprisal are proportionality - to make clear that the response is proportionate to the immediate offense - and publicity - to make clear to the other side that this is a lawful action as legal reprisal, not merely retaliation in a military sense, a formal move in the law of war intended to return to the status quo. It is intended to stop short of full belligerency, in which the war aims shift, and proportionality is no longer measured by the immediate provocation, but by a state's assessment of the underlying threat.

One can think of many situations in the world where the law of belligerent reprisal plays an important role. India and Pakistan, for example, have long engaged in such reprisal exercises. But it is important to understand that proportionality in the law of belligerent reprisal is not measured against the same standard as proportionality where the casus belli is an underlying and much broader threat. Proportionality is measured not against each separate rocket attack, one after another, none individually rising to the level of a response of open war, but against the whole series and the on-going threat they pose. My reading of much of the commentary on proportionality in the debate over Israel and its war aims suggests to me that many are applying a standard of belligerent reprisal proportionality when, in fact, what is at issue is the elimination of the underlying threat.

***Here is my original pre-Instalanche post:

... I really am pressed on some other things, but - proportionality jus ad bellum is perhaps best understood as a species of reprisal - i.e., a retaliatory measure which is proportionate to the original harm committed and limited as a proportionate response because, legally, it is a form of self-help with the purpose of preventing a spiraling response-counterresponse. The legal idea of reprisal, as distinguished from retaliation, is proportionality, which is intended to draw the originally offending party back to the legal status quo. It has, however, only limited applicability in the tradition of jus ad bellum; it is the exception rather than the rule, because in many circumstances, the threat presented by the status quo itself, of which the specific instance of harm is merely representative, is the casus belli. It is not necessarily cured by a response which is merely proportionate to the narrow and specific triggering belligerent act - a provocation across the border, for example. Proportionality in jus ad bellum is a legal concept appropriate not to belligerency in the full sense - in that case, war aims lawfully include bringing the oppposing party to surrender - but to the much narrower situation of uses of force short of full belligerency. Legal scholars who want to focus on the UN Charter as the sole source of legal authority for the use of force - and hence see any armed action by a party as having to be 'proportionate' pending some (typically mythological) intervention by the Security Council - tend to underplay that the Charter does not remove the customary law of self-defense, which does not require a "proportionate" response once belligerency is underway. Proportionality in jus ad bellum is a far narrower legal concept with far narrower application as a matter of the law of belligerent reprisal.