Preventive war and the U.S. attack on Iran

Last week I argued that the U.S. should stay out of Israel’s war with Iran. America has now entered the war by bombing three facilities associated with Iran’s nuclear program. Is this action morally justifiable in light of traditional just war doctrine?

War aims?

Let us note, first, that much depends on exactly what the U.S. intends to accomplish. A week ago, before the attack, President Trump warned that Tehran should be evacuated, called for Iran’s unconditional surrender, and stated that the U.S. would not kill Iran’s Supreme Leader “for now”—thereby insinuating that it may yet do so at some future time. Meanwhile, many prominent voices in the president’s party have been calling for regime change in Iran, and Trump himself this week has joined this chorus. If we take all of this at face value, it gives the impression that the U.S. intends or is at least open to an ambitious and open-ended military commitment comparable to the American intervention in Iraq under President Bush.

As I argued in my previous essay, if this is what is intended, U.S. action would not be morally justifiable by traditional just war criteria. I focused on two points in particular. First, the danger such intervention would pose to civilian lives and infrastructure would violate the just war condition that a war must be fought using only morally acceptable means. Second, given the chaos regime change would likely entail, and the quagmire into which the U.S. would be drawn, such an ambitious intervention would violate the just war condition that a military action must not result in evils that are worse than the one being redressed.

However, it is likely that we should not take the president’s words at face value. He has a long-established tendency to engage in “trash talk” and to make off-the-cuff remarks that reflect merely what has popped into his head at the moment rather than any well-thought-out or settled policy decision. Furthermore, even when he does have in mind some settled general policy goal, he appears prone to “making it up as he goes” where the details are concerned (as evidenced, for example, by his erratic moves during the tariff controversy earlier this year). My best guess is that he does not want an Iraq-style intervention but also does not have a clear idea of exactly how far he is willing to go if Iran continues to resist his will.

As I said in my previous essay, this is itself a serious problem. An erratic and woolly-minded leader who does not intend a wider war is liable nevertheless to be drawn into one by events, and can also cause other harm, short of that, through reckless statements.

But so far, at least, the U.S. has in fact only bombed the facilities in question. Suppose, for the sake of argument,t that this limited “one and done” intervention is all that is intended. Would this much be justifiable under just war doctrine?

Preemptive versus preventive war

This brings us to an issue which I only touched on in my earlier essay but which is obviously no less important (indeed, even more important) than the two criteria I focused on: the justice of the cause for which the war is being fought, which is the first criterion of just war doctrine. The reason I did not say more about it is that the issue is more complex than meets the eye. I think Israel can make a strong case that its attack on Iran’s nuclear program meets the just cause condition for a just war. But it is harder for the U.S. to meet that condition, even in a “one and done” scenario.

To understand why, we need to say something about a controversy that arose during the Iraq War and is highly relevant to the current situation, but hasn’t received the attention it ought to. I refer to the debate over the morality of preventive war, which ethicists often distinguish from preemptive war.

In both preemptive war and preventive war, a country takes military action against another country that has not attacked it. And in both cases, the country initiating hostilities nevertheless claims to be acting in self-defense. This might seem like sophistry and a manifest violation of the just cause criterion of just war doctrine. How can a country that begins a war claim self-defense?

But there is a crucial difference between the two cases. In a preemptive war, country B is preparing to attack country A but has not in fact yet done so. Country A simply preempts this coming attack by striking first, and can claim self-defense insofar as country B was indeed going to attack it. By contrast, in a preventive war, country B was not preparing to attack country A. But country A attacks country B anyway, claiming that country B likely would pose a threat to A at some point in the future.

Now, it is generally acknowledged among ethicists that preemptive war can sometimes be morally justifiable. But preventive war is much more problematic and controversial. There are two main traditions of thinking on this subject (a useful overview of which can be found in chapter 9 of Gregory Reichberg’s book Thomas Aquinas on War and Peace). On the one hand, there is the natural law tradition of thinking about just war criteria, associated with Scholastic Catholic writers like Thomas Aquinas and Francisco de Vitoria, Protestants like Hugo Grotius, and more recent Thomists like the nineteenth-century Catholic theologian Luigi Taparelli. According to this tradition, preventive war is flatly morally illegitimate. It violates the principle that a person or country cannot be harmed merely for some wrong it might do, but only for some wrong that it has in fact done.

The other main approach is the “realist” tradition associated with Protestant thinkers like Alberico Gentili, Francis Bacon, and (with qualifications, since he also drew on the natural law tradition) Emer de Vattel. As Reichberg notes, whereas the natural law approach takes the international order to be governed by the moral law just as relations between individuals are, the tendency of the realist tradition is to look at the international arena in something more like Hobbesian terms. And the realist tradition is thus more favorable to preventive war as a tool nations might deploy as they negotiate this Hobbesian state of nature.

As Reichberg also notes, Vattel put the following conditions on the justifiability of some country A’s initiating a preventive war against another country B. First, country B must actually pose a potential threat to country A. Second, country B must threaten the very existence of country A. Third, it must intend to pose such a threat. And fourth, it must somehow have actually shown signs of evildoing in the past. Vattel adds the condition that country A must first have tried and failed to secure guarantees from country B that it will not attack A.

Much of the controversy over the Iraq war had to do with whether a preventive war is morally justifiable, and the Bush administration did sometimes say things that implied that the war was preventive in nature. But as I argued at the time, this particular aspect of the debate was a red herring. The main rationale for the war was that Saddam had not complied with the terms of the ceasefire of the Gulf War, so that the U.S. and her allies were justified in restarting hostilities in order to force compliance. Whatever one thinks of this as a rationale, it is not an appeal to preventive war. Hence, any criticism of the Iraq war should, in my view, focus on other aspects of it (such as the intelligence failure vis-à-vis WMD and the folly of the nation-building enterprise the war led to).

The case of Iran

What matters for present purposes, though, is the relevance of all this to the war with Iran. Now, it was Israel rather than Iran that initiated the current hostilities. Was this morally justifiable?

It seems clear to me that it was justifiable by Vattel’s criteria for preventive war. But as a natural law theorist, I don’t think preventive war can be justified, so that particular point is moot. However, that does not entail that it was wrong for Israel to attack Iran’s nuclear program. For it can plausibly be seen as a justifiable preemptive rather than preventive attack. To be sure, Iran was not preparing a specific nuclear attack operation, since it does not have nuclear weapons. But Israel can make the following argument: Iran has already been in a state of war with Israel for years; its leadership has repeatedly threatened Israel’s destruction; if it acquired nuclear weapons, it would actually be capable of carrying out this threat; and it has for years been trying to acquire them. Destroying its nuclear program is therefore not merely a preventive action, but in the relevant sense an act of preempting an attack (in its very earliest stages, as it were) that Israel has good reason to think Iran intends.

This seems to me a strong argument, so I think that Israel can indeed make the case that it has a just cause, at least insofar as its aim is simply to destroy Iran’s nuclear program. (A more ambitious goal of regime change would be much harder to justify, for the same reason that, as I said in my earlier article, it would not be justifiable for the U.S. to attempt regime change. But here I am just addressing the more limited aim of destroying Iran’s nuclear capability.)

However, this does not entail that the U.S. is justified in attacking Iran. Note first that the recent U.S. bombing was not carried out in response to any act of war on Iran’s part against the United States. True, some have pointed out that U.S. and Iranian-backed forces have been involved in various skirmishes in recent decades. But it would be dishonest to pretend that that had anything to do with the recent U.S. action. If Iran’s nuclear program had not been in the picture, Trump would not have ordered the bombing. Hence, if the U.S. is claiming to be acting in justifiable self-defense, it could plausibly do so only by the criteria governing preemptive war or preventive war.

But in fact, it cannot plausibly do so. Note first that the U.S. action does not meet even Vattel’s criteria for preventive war. For even if Iran already had nuclear weapons, it would not pose a threat to the very existence of the United States (the way it would pose a threat to the very existence of Israel). For one thing, Iran lacks any plausible means of getting a nuclear device into the United States; for another, even if it could do so, it would hardly be able to destroy the country as a whole. Hence, any “preventive war” case for U.S. self-defense is fanciful. And if that is true, then it is even more obvious that the U.S. cannot plausibly meet the more stringent criteria for a preemptive war case. Iran simply cannot plausibly be said to have been in the process of planning a nuclear attack on the U.S., even in the looser sense in which it might be said to have been planning such an attack on Israel.

I conclude that no serious case can be made that the U.S. attack on Iran was a justifiable act of self-defense. However, there is one further way the attack might seem to be justified. Couldn’t the U.S. argue that, even though it couldn’t plausibly hold that it was defending itself, it was justifiably helping its ally Israel to defend itself?

Certainly, it can be justifiable to help an ally defend itself. But whether it ought to do so in any particular case depends on various circumstances. For example, suppose Iran actually had a nuclear weapon, and it was known that it was about to deploy it against Israel and that only the U.S. could stop the attack. I would say that in that sort of scenario, the U.S. not only could intervene to stop such an attack but would be morally obligated to do so. And it would also be morally justifiable for the U.S. to intervene in order to help Israel in other, less dire scenarios.

But we are not now in a situation remotely close to such scenarios. There are various ways Israel could stop Iran’s nuclear program by itself–as it appears Israeli Prime Minister Benjamin Netanyahu has acknowledged. Meanwhile, there are serious potential downsides to U.S. involvement. American troops could be killed by Iranian retaliatory strikes, the U.S. economy could be hit hard if Iran closes off the Strait of Hormuz, and if the Iranian regime were to collapse the U.S. could be drawn into a quagmire in attempting to mitigate the resulting chaos. Yes, such things might not in fact happen, but they plausibly could happen, and keeping one’s fingers crossed is not a serious way to approach the application of just war criteria. If Israel doesn’t strictly need the U.S. to intervene and intervention poses such potential risks to U.S. interests, then the U.S. should not intervene.

Hence, I am inclined to conclude the following about the U.S. attack, even if (as we can hope) it does indeed turn out to be a “one and done” operation. Was the American bombing of Iranian nuclear facilities intrinsically wrong? No. But did it meet all the conditions of just war doctrine, all things considered? No.

(Editor’s note: This essay was first posted, in slightly different form, on the author’s blog on June 23. It is posted here with the kind permission of the author.)