In talking about the present nuclear threat, it paradoxically is important to go back to the beginning of the nuclear age. A striking fact is that the choices were well understood at the outset. "Strategists" and physicists saw very clearly, for example, that either there would be international control of the materials to make the bomb, or that a nuclear balance of terror would emerge. Fatefully, it was the second path that was taken, led by the United States.

Single most important facts of the nuclear age: Hiroshima and Nagasaki. US dropped atomic bombs on a country that itself had no atomic bombs, nor certainly was not going to defeat the United States. The only question was how long would Japan’s defeat take. Here’s another very important fact: the Soviet Union had entered the war. I repeat, the Soviet Union had entered the war.

Any assessment of reducing the role of nuclear weapons in security doctrines, the subject of the panel discussion today and called for by the 2000 NPT Review Conference Final Document ("steps ... leading to nuclear disarmament" include "a diminishing role for nuclear weapons in security policies to minimize the risk that these weapons ever be used and to facilitate the process of their total elimination"), should start with their actual use in war. The International Court of Justice did this, by the way. Nowhere in the opinion do you find Hiroshima and Nagasaki mentioned. But you do find the clear statement that humanitarian law barring the infliction of indiscriminate harm and unnecessary suffering preceded the nuclear age. That means the bombings were illegal. If you were there when oral arguments were made, as I was, the fact that ICJ dealt clearly, if in subtext, with the bombings of the two cities would not surprise you. The testimony of the mayors of Hiroshima and Nagasaki had an enormous impact, including on the judges.

Another striking fact at the commencement of the nuclear age: the development of the atomic and hydrogen bombs, the creation of the computer, and the advent of game theory, the highly elaborated instrumental thinking that would form the basis of deterrence theory, all were intertwined and reinforcing. And they were even embodied in one person, said to be a genius, John von Neumann, who directed the building of a computer at Princeton, who was a principal founder of game theory, and who was one of the Manhattan Project physicists.

Now some fifty-five years later, there has been a resurgence of normative thinking and an understanding that a normative framework must replace the game theory, the instrumental thinking, the deterrence theory that have dominated thinking about nuclear weapons.

By a normative framework I mean simply moral and legal rules and principles. I say "moral" without embarrassment. We have stared too long into the abyss, the utter nihilism, of entrusting security and our souls to stark calculations of power, of interest. Does not the phrase "balance of terror" say it all?

Morality means, among other things, accepting that there are categorical, absolute norms. It is not acceptable to use gas ovens to annihilate a people. It is not acceptable to threaten or carry out mass destruction of civilian populations.

And the moral and legal norms are interrelated, self-reinforcing.

The resurgence of normative thinking is generally evident in the establishment of the international criminal tribunals for the former Yugoslavia and Rwanda, and in the negotiation of the Statute of the International Criminal Court.

In the nuclear field, of course, the resurgence of normative thinking is exemplified by the advisory opinion of the International Court of Justice on the legality of threat or use of nuclear weapons.

Let me offer an authoritative, and too much neglected, application of the opinion, by persons extremely well versed in the realities of nuclear weapons and deterrence doctrines. That is found in the 1997 study carried out by the Committee on International Security and Arms Control of the National Academy of Sciences, The Future of U.S. Nuclear Weapons Policy. The Committee stated regarding the ICJ opinion:

[T]he ICJ unanimously agreed that the threat or use of nuclear weapons is strictly limited by generally accepted laws and humanitarian principles that restrict the use of force. Accordingly, any threat or use of nuclear weapons must be limited to, and necessary for, self defense; it must not be targeted at civilians, and be capable of distinguishing between civilian and military targets; and it must not cause unnecessary suffering to combatants, or harm greater than that unavoidable to achieve military objectives. In the committee’s view, the inherent destructiveness of nuclear weapons, combined with the unavoidable risk that even the most restricted use of such weapons would escalate to broader attacks, makes it extremely unlikely that any contemplated threat or use of nuclear weapons would meet these criteria.

When discussing the ICJ opinion, we must, however, squarely confront the problems posed by the Court’s inability to reach a definitive conclusion regarding an extreme circumstance of self-defense in which the very survival of a state is at risk. Relatedly, the ICJ also asserted generally that it would not deal with the lawfulness of deterrence.

First observation: here is an anachronistic element of instrumental thinking, proof of its continuing influence. I believe that what the Court was wrestling with, or more precisely the three majority judges only who, however reluctantly, affirmatively supported the formulation, is not so much that the use of nuclear explosives in such a circumstance might be justified, that the threat might be so, in order to prevent immeasurable suffering and destruction.

Second observation: Nonetheless, in the majority opinion, and in the separate statements of a large majority of the judges, the Court clearly affirmed that any threat or use must comply with the fundamental norms of humanitarian law. Always to be emphasized here is the unambiguous statement of the following "fundamental" and "intransgressible" principle: "States must never make civilians the object of attack and consequently never use weapons that are incapable of distinguishing between civilian and military targets".

Third observation: The extreme circumstance provision was only – only – a statement of inability to reach a conclusion, and in no way a recognition of the legitimacy of threat or use in such a circumstance. The remarks of President Bedjaoui underlining this simple point are critical here. I wish to draw attention to a little remarked statement of Bedjaoui’s: The opinion reflects "a current trend towards the replacement of one rule of international law by another, where the first is already defunct and its successor does not yet exist". Here Bedjaoui is saying that the norm of absolute prohibition of threat or use is emerging.

This is not just idle chatter on Bedjaoui’s part. Let me give an example. In the negotiation of Protocol I to the Geneva Conventions, the nuclear weapon states resisted subjecting nuclear weapons to developing international law regarding environmental damage. For this reason, the Court while noting the relevance of environmental consequences in assessing the necessity and proportionality of threat or use of nuclear weapons had been unable to clearly state a universally binding rule.

But just two years after the advisory opinion, we find the following rule accepted, including by US negotiators, as binding customary law in the Statute of the International Criminal Court: it is a war crime to intentionally launch an attack in the knowledge that it will cause "widespread, long-term and severe damage to the natural environment which would be clearly excessive in relation to the concrete and direct overall military advantage anticipated".

Now let us apply the normative framework represented but not wholly captured by the ICJ opinion to present day deterrence doctrines.

First, the threat of certain massive retaliation against nuclear attack. For the United States, at least, this threat is based on targeting of nuclear facilities, other military capabilities, and allegedly war-related industry and infrastructure. It is not targeting of civilian populations per se. As General Lee Butler has pointed out, this is a plan which makes most sense if executed preemptively. So massive retaliation is operationally closely associated with the maintenance of a first strike capability.

But massive retaliation, whether as a matter of first or second use, causes civilian injury and death at the same order of magnitude as a direct attack on civilian populations. So it is clearly barred by the prohibition of the infliction of indiscriminate harm.

Second, the option of first use in response to an overwhelming conventional attack. It is doubtful this option can meet the requirements of necessity and proportionality. In any event, it would violate the rules protecting civilians and combatants against indiscriminate and unnecessary harm, and the rules protecting neutral nations and the environment.

Third, the option of first use in defense of vital interests. Illegal for the same reasons, and in most cases also barred by the negative security assurances given parties to NWFZS and to the NPT.

Fourth, the option of first use in response to the threat or use of chemical and biological weapons. This of course is the scenario that has been most prominent in efforts in the United States to relegitimize nuclear weapons. No one should underestimate the strength of these efforts. Again illegal for the same reasons, the prohibitions of inflicting indiscriminate harm, unnecessary suffering, damage to the environment, harm to neutral nations, etc. Arguably also contrary to negative security assurances, though this is not as clear as one might like in the case of an actual attack with chemical or biological weapons where a nuclear response could be defended as a reprisal aimed at stopping further illegal attacks with chemical or biological weapons.

Compare here the law on retaliatory use of chemical and biological weapons. Clearly prohibited in the case of chemical weapons; the CWC says chemical weapons "shall never in any circumstance" be used. No such clear prohibition in the case of biological weapons, but one never hears the argument that biological reprisals are permissible.

So why should nuclear reprisals, in any circumstance, still less nuclear preemptions, be permissible? They should not be, and under the emerging rule identified by Bedjaoui, they are not.

What then of "reducing the role of nuclear weapons in security doctrines"? One can propose that the inviolability of negative security assurances be recognized and legally confirmed, including in the case of chemical or biological attacks; that the option of first use in defense of vital interests or against overwhelming conventional attack be repudiated; that the doctrine of certain massive retaliation against nuclear attack be abandoned. This would leave, at most, extremely selective nuclear response to a nuclear attack, aimed only at stopping further nuclear attacks; the recommendation of the National Academy of Sciences committee.

And much discussion of "reducing the role of nuclear weapons in security doctrines" proceeds along these lines. I wish to leave you with the following question, however. Did the ICJ have it right in saying that at present the only uncertainty resides with respect to an attack jeopardizing the very survival of a state? And with some imagination, it must be admitted that such attacks can come in a variety of forms – they need not only be nuclear. And therefore, is it not the case that the "reducing the role of nuclear weapons in security doctrines" must, as is true now of chemical and biological weapons, boil down to the conclusion that nuclear weapons must never be used or threatened to be used, whatever the circumstance? That this is the emerging rule alluded to by Bedjaoui. And that this rule leads, as it does for chemical and biological weapons, as the ICJ unanimously recognized, to a recognition of the imperative of eliminating nuclear weapons globally as the companion to the imperative of non-use?

I end with the words of Judge Weeramantry, who identified, like Bedjaoui, the direction of the Court’s opinion: "A global regime which makes safety the result of terror and can speak of survival and annihilation as twin alternatives makes peace and human future dependent upon terror. This is not a basis for world order which this Court can endorse." Neither can we endorse terror as a basis for world order. The only viable basis is a reaffirmation of the centrality of morality and law.