Norms in nuclear (in)action

Tannenwald could scarcely have chosen a more important topic to study. The non-use of nuclear weapons, she rightly declares, ‘remains the single most important phenomenon of the nuclear age’.Footnote ² It is also the most puzzling. By the end of the Cold War, the nuclear powers had amassed nearly 70,000 nuclear weapons yet none had been used since 1945. This is all the more remarkable given nuclear weapons were widely credited with forcing Japan to surrender and thereby ending WWII. As Tannenwald notes, somewhat dryly: ‘it is rare for a weapon found useful on one occasion to remind unused in the next’.Footnote ³ Nuclear deterrence is the standard explanation for nuclear non-use. That is to say, the US and Soviet Union were deterred from using nuclear weapons against each other by the threat of nuclear retaliation; deterrence would have operated similarly to discourage Britain, France and China from using nuclear weapons. But what about cases where states without nuclear weapons have attacked nuclear-armed states, such as, Argentinan's invasion of the British Falkland Islands in 1982. To retake the islands involved a massive effort and a very risky military campaign by Britain: one that stretched Britain's conventional force projection capabilities to breaking point. It would have been much easier for Britain to retaliate with nuclear weapons. But Argentina never feared this. Why?Footnote ⁴

Tannenwald proposes that ‘a powerful taboo against the use of nuclear weapons has developed in the global system’ that ‘has stigmatized nuclear weapons as unacceptable weapons’.Footnote ⁵ The nuclear taboo is a moral rather than a legal norm: there is no international treaty specifically outlawing the use of nuclear weapons. Though various legal agreements on nuclear arms control and nuclear-weapons free zones have chipped away at the legality of nuclear weapons and contributed to the de-legitimatisation of this class of weapons.Footnote ⁶ The nuclear taboo would go some way to explaining why non-nuclear states would not fear that nuclear weapons would be used against them in war. But, crucially, Tannenwald is not arguing that the taboo can by itself explain all cases of non-use of nuclear weapons since 1945. Rather her argument is that nuclear deterrence and nuclear taboo have operated synergistically to produce American nuclear non-use. To prove her argument, Tannenwald explores US decision-making in three wars against non-nuclear opponents: the Korean War, Vietnam War and 1991 Gulf War. The inference (explored in the final chapters of the book) is that the nuclear taboo has operated to also inhibit other states from acquiring and using nuclear weapons.

So how has this norm against nuclear use worked? Constructivists generally recognise norms as working in two ways to shape actors and action in world politics. First, norms regulate action by telling actors what is possible (given moral codes and the laws of science).Footnote ⁷ This view of norms is consistent with the rationalist perspective of a world structured by rules and institutions that enable states to coordinate activities as required and to collaborate to mutual benefit.Footnote ⁸ Constructivists also see norms as operating at a deeper level to constitute social situations and the identities of actors. In this sense, norms go ‘all the way down’ to shape the ends (that is, the self-interests that are derived from identities) as well as means of social action.Footnote ⁹ Thus, for constructivists, norms not only facilitate rational action, they also work at a more profound level to make meaningful action possible. Tannenwald suggests that the Nuclear Taboo constitutes nuclear weapons as ‘unacceptable weapons of mass destruction’, the ‘practice of stable nuclear deterrence’ as appropriate behaviour for nuclear armed opponents, and nuclear-use as inconsistent with the identity of a ‘civilized state’ and unacceptable in the civilised world.Footnote ¹⁰

In addition to regulative and constitutive effects, Tannenwald proposes a third way that norms work which is by producing permissive effects: By this she means ‘the way that norms – taboos in particular – by serving as focal points, selectively divert our normative gaze’.Footnote ¹¹ Permissive effects are indirect, ‘shadow’, and often unintended effects of the norm. Hence, a permissive effect of the nuclear taboo ‘may be to shield non-nuclear weapons from normative opprobrium’.Footnote ¹² This conceptual innovation by Tannenwald has relevance to many other areas of world politics. For instance, it may be applied to the law of armed conflict (LOAC). This body of law evolved from a Western tradition of practical ethical reasoning based on Christian theology and medieval military custom, into highly technical and codified rules on the conduct of warfare.Footnote ¹³ However, the manner of their enforcement has focused normative attention on those cases (for example, the civil wars in Rwanda and Yugoslavia) where violence against civilians is integral to the mode of warfare. All the while, Western states have practiced high-tech warfare that is legal in the technical sense but may be unethical nonetheless.Footnote ¹⁴ The point is that Western bombing campaigns, however precise, can still cause massive infrastructural damage, especially when directed against ‘dual-use’ targets (that is, targets such as roads, railways and bridges, which can have military application but are often essential to civilian life), and in so doing may cause huge population displacement and increased mortality.Footnote ¹⁵ The LOAC regulates, constitutes and permits the conduct of such ‘civilised’ warfare.

Returning to Tannenwald's taboo: three specific mechanisms are identified by which it has taken effect in US policy: domestic public opinion, world opinion, and the personal moral convictions of individual leaders.Footnote ¹⁶ It is notoriously difficult to demonstrate the causal impact of public opinion on specific policy outcomes because policy elites often seek to shape and strategically use public opinion to support their preferred courses of action. Indeed the 2003 Iraq War provides a dramatic example of the ability of policy elites to build public support for the preferred policy by controlling information and framing the issue.Footnote ¹⁷ The level of international public opposition to the 2003 Iraq War does show that world opinion is less open to manipulation by US policy elites, but it also suggests that US policymakers pay little heed to it. However, Tannenwald produces plenty of evidence that US policymakers during the Cold War were sensitive to public and world opinion, the overwhelming weight of which was against first nuclear use. Hence when fears were raised in late 1950 that the US was considering the use of atomic weapons in the Korean War, US embassies the world over reported that such action would be greeted by public ‘horror and antipathy’.Footnote ¹⁸ Well into 1951 the US State Department continued to track public opinion around the world on this issue and to report public opposition in the strongest terms: ‘a general public repugnance to the use of the weapon under any but the most dire circumstances’ was the view from France, even though France was wrestling with its own Asia problem at the time.Footnote ¹⁹ Thus, whilst President Dwight Eisenhower and Secretary of State John Foster Dulles were both open to the possibility of nuclear use in the Korea War, they still felt constrained by the depth of public opposition to nuclear use. Tannenwald produces compelling evidence also pointing to the role of personal convictions. She shows that the senior US leadership responsible for prosecuting the Vietnam War under President Lyndon Johnston (namely, the President, Secretary of Defence Robert McNamara, and Secretary of State Dean Rusk), shared an abhorrence of nuclear weapons, and a determination not to use nuclear weapons against a non-nuclear opponent.Footnote ²⁰ By the 1991 Gulf War, first use of nuclear weapons had become simply unthinkable for the civilian and military leadership alike.Footnote ²¹

This is not to say that US policy elites slavishly followed public opinion during the Cold War. Policy elites resisted growing public opposition to the Vietnam War.Footnote ²² And so it was on the particulars of nuclear strategy. The Eisenhower administration pursued a nuclear policy of massive retaliation (that is, threatening to respond to any Soviet attack with an all-out nuclear strike) despite the fact, as President Eisenhower told his Secretary of State, ‘as much as two-thirds of the world and 50 per cent of US opinion’ opposed it.Footnote ²³ But on the key question of actually using nuclear weapons, Eisenhower and Dulles found themselves trapped by the nuclear taboo. Given the three causal mechanisms identified by Tannenwald, she argues that the nuclear taboo may operate more effectively in democracies than in non-democratic states. Hence, Tannenwald concludes that in the case of the Korean War ‘American democratic structures and political values made US leaders react to public opinion pressures and moral concerns in a way that leaders of an authoritative state would not.’Footnote ²⁴ However, in this case, reinforcing foreign public opposition to the use of atomic weapons was diplomacy by allied and neutral countries. The allies, in particular, were active and (it would appear) effective in discouraging the US from escalating the war following China's entry in support of North Korea.Footnote ²⁵ This suggests that perhaps a fourth mechanism was at play: namely, allied diplomacy. Of course, allies have not always sought or been able to restrain the US. Nonetheless, the inference from Cold War history is that the nuclear taboo is most effective in an alliance of democracies.

The rise and limits of the nuclear taboo

The notion that there is some sort of taboo surrounding nuclear weapons use is widely accepted today. As Tannenwald notes: ‘[n]o one today views a nuclear weapon as “just another weapon”’.Footnote ²⁶ But it was not always so. When once Sweden and Switzerland assumed they would need to acquire nuclear weapons to defend their neutrality, now neither would dream of ‘going nuclear’. Similarly, when once states planned, exercised, and developed the capabilities for tactical nuclear use,Footnote ²⁷ now using such weapons on the battlefield is inconceivable. So how did the nuclear taboo evolve?

Tannenwald identifies six mechanisms whereby the nuclear taboo has developed: (1) ‘societal pressure’ from domestic and transnational social groups (such as the nuclear freeze movement); (2) ‘normative power politics’ whereby states seek through rhetoric and diplomacy to de-legitimise nuclear weapons; (3) norm entrepreneurship by individual state leaders; (4) ‘iterative behaviour over time’ resulting in a state custom against nuclear use; (5) institutionalisation of anti-nuclear norms in formal rules and conventions and, (6) ‘the role of historical contingency’, such as Truman's ‘post-Nagasaki abhorrence of nuclear weapons’. Although she does not express it as such, in this mix Tannenwald is proposing two bottom-up mechanisms (societal pressure and state custom) and two top-down mechanisms (norm entrepreneurship and normative power politics) of norm development. As she shows in her case studies, these six mechanisms operated to different degrees at different times to ‘shift the discourse on nuclear weapons’ and gradually develop the norm against nuclear use.Footnote ²⁸

Overall, Tannenwald argues that the nuclear taboo developed in two main stages – a period between 1945 and the end of the 1950s during which the norm emerged, and the period from the 1960s on during which the taboo became institutionalised and internalised. Framing these periods are two triggering events: namely the atomic bombing of Japan and the Cuban Missile Crisis in October 1962. The scale of death and destruction in Hiroshima and Nagasaki was far greater than anticipated by US leaders. The immediate death toll from the two bombs was expected to be 20,000: it turned out to be seven times this amount. Truman was truly shocked by this. A few days later he told his budget director that he was not sure the atomic bomb could ever be used again.Footnote ²⁹ Truman thereafter acted as a norm entrepreneur, in rejecting military plans for preventive atomic war against the Soviet Union and in institutionalising civilian control of nuclear weapons. Hence, Truman prompted Congress to pass the Atomic Energy Act in 1946, which took nuclear weapons out of military hands and placed them in the custody of a new civilian agency, the Atomic Energy Commission.Footnote ³⁰ Tannenwald also points to the Cuban Missile Crisis as a critical event in alerting US and Soviet leaders to ‘the dangers of an unchecked arms race and the overwhelming imperative to avoid nuclear war between them’.Footnote ³¹ These events probably fall under Tannenwald's sixth mechanism of norm development, namely, historical contingency. But it is curious that in identifying the mechanisms of norm evolution, she does not highlight the role of external shock.Footnote ³² And in this respect, she does not dwell in any details on the Cuban Missile Crisis. In contrast, a number of constructivist theorists have emphasised the role of traumatic events which cause communities to question conventional ways of thinking and doing, as significant triggers of cultural change.Footnote ³³ Hence, it has been argued that the utter defeat of Germany and Japan in WWII shocked both polities into developing anti-militaristic strategic cultures.Footnote ³⁴ Few events can have been as shocking for US policymakers as the prompt devastation of Hiroshima and Nagasaki, and the prospect that even greater destruction might be unleashed on American cities seventeen years later.Footnote ³⁵

Tannenwald makes a persuasive case for the rise of the nuclear taboo in civilian policy. But this gives us only half the picture. What about the US military? Well the military did not consider nuclear weapons to be special weapons of last resort. Quite the opposite. In its first war plan drawn up in 1949, Strategic Air Command (SAC) intended to rapidly deliver the entire nuclear arsenal at one go, dropping 133 atomic bombs on 70 Soviet cities. SAC thinking on this was informed by the experience of WWII, specifically the bombing of German and Japanese cities. The same officers who planned and led the US Army Air Force's (USAAF) city-bombing campaigns took their ideas about air war with them into the newly formed SAC.Footnote ³⁶ And these officers were not at all squeamish about blasting and burning cities to the ground. The USAAF bombing of Japan destroyed 65 per cent of the cityscape and killed between 400,000 and 900,000 civilians. These early nuclear war plans do not contradict Tannenwald's case because she argues that the nuclear taboo was weak in this embryonic stage. But my point is (and this is where the contradiction becomes apparent) that these early SAC operational preferences for a massive all-out strike and for targeting cities became encoded in subsequent nuclear war plans including, from 1960 on, in the Single Integrated Operational Plan (SIOP).Footnote ³⁷ Civilian efforts to introduce more restraint and limited strike options into the SIOP had little effect. The SIOP was so technical and so secret that it evaded civilian oversight. As one authoritative study concluded, the SIOP was ‘virtually etched in stone’, leaving civilian policymakers ‘bound by the contours of the war plan rather than the other way around’.Footnote ³⁸

It might be argued that however the military thought about or planned for nuclear war, the important thing was that civilian decision-makers felt bound by the nuclear taboo. However, civilian control over nuclear use was far from secure during the Cold War. In the early decades the US Air Force favoured a showdown with the Soviet Union whilst the US enjoyed a vast superiority in strategic nuclear forces. There is even evidence to suggest that SAC sought to provoke a war by stunts such as flying bombers into Soviet airspace.Footnote ³⁹ By the late 1960s the Soviets had acquired a sufficiently large nuclear arsenal to discourage SAC from seeking war. But there were still repeated failures in America's early warning system and in nuclear custodianship, any of one of which might have triggered a chain of events leading to accidental nuclear use.Footnote ⁴⁰ Compounding this risk, in the early 1970s, SAC adopted a launch on warning (LOW) posture because of concerns that a Soviet first strike might knock out the US command and control system. This meant that instead of waiting for mushroom clouds over the US and then retaliating, SAC planned to launch its entire arsenal in a massive pre-emptive strike (nuclear planners called this the ‘Midnight Express’) on confirmation of an incoming Soviet nuclear attack.Footnote ⁴¹ Obviously, LOW put added pressure on the accident prone US early warning system.

Fortunately, the nuclear taboo (and so the world) survived the Cold War intact. But what of the future prospects of this norm? Tannenwald is optimistic. She points to the work of antinuclear activists and to the establishment of nuclear weapons-free zones by states in the South, as further strengthening the nuclear taboo. However, there have also been setbacks not sufficiently recognised by Tannenwald. Indeed, she spins one setback as ‘the highpoint of the [nuclear] abolition movement’; namely to get the International Court of Justice (ICJ) to issue an advisory opinion on the legality of nuclear use,Footnote ⁴² which it did in 1996. Such an opinion would not be legally binding on states, but it would carry enormous authoritative weigh in international law. In considering the principles of proportionality and discrimination, the Court found nuclear use (and therefore also the threat of such use) to be generally unlawful. However, it was unable to ‘definitely conclude’ that nuclear use would be unlawful in all circumstances, in particular, those involving ‘extreme circumstances of self-defence’, and ‘clean use’ of small nuclear weapons against isolated military targets (such as naval targets in the deep ocean). Self-defence is one of two exceptions to the non-use of force rule in international law (the other being UN authorised use of force to protect international peace and security). However, the law does not distinguish between degrees of self-defence, and regardless any use of force must be proportionate and must discriminate between military and civilian targets. The essential problem, as the Court recognised, was the very great risk that nuclear use would escalate to a level that was disproportionate and indiscriminate. In this respect, the Court also expressed very serious misgivings about ‘clean nuclear use’ scenario. But in the end the ICJ declared that it lacked the information to pronounce on whether or not nuclear weapons are inherently incapable of discriminating between civilian and military targets in all circumstance. Far from being a ‘powerful symbol’ reinforcing the nuclear taboo,Footnote ⁴³ this was a muddled advisory opinion, the authority of which was further compromised by the fact that the Court was evenly split on it, and the opinion was only adopted by the deciding vote of the ICJ President.Footnote ⁴⁴

Another setback, the 2002 Nuclear Posture Review (NPR), receives too little attention from Tannenwald. This review was conducted in light of the renewed emphasis post 9/11 on the threat from weapons of mass destruction (WMD) proliferation. The 2002 NPR presented three challenges to the nuclear taboo. First, it called for plans to be drawn up for nuclear use against rogue states, all of which were non-nuclear at the time. Two are still non-nuclear (Syria and Libya), one is no-longer a rogue state (Iraq), one has tested a primitive nuclear weapon (North Korea), and one is on the verge of acquiring nuclear weapons (Iran). This new targeting priority was subsequently authorised in civilian guidance on nuclear employment, that is, National Security Presidential Directive 17 (NSPD 17). NSPD 17 also instructed Strategic Command (STRATCOM – the successor to SAC) to develop plans for nuclear retaliation for chemical or biological attacks.Footnote ⁴⁵ Moreover, senior US officials refused to rule out first nuclear use in the 2003 Iraq War, and indeed STRATCOM produced a ‘Theatre Nuclear Planning Document’ for the campaign. This new direction in US nuclear war planning breached a long-standing US guarantee (called the Negative Security Assurance) not to threatened non-nuclear states with nuclear attack: the whole of point this assurance was to give such states less reason to acquire nuclear weapons of their own.Footnote ⁴⁶

The second challenge presented by the 2002 NPR was the integration of conventional and nuclear assets in a single unified strike force. The commander of STRACOM testified to the Senate Armed Services Committee that this development would ‘raise the nuclear threshold by providing the President with strategic options in a crisis or conflict that do not rely solely on nuclear weapons’.Footnote ⁴⁷ Critics saw things differently; that by lumping conventional and nuclear weapons together the line between the two might be more easily crossed than in the past.Footnote ⁴⁸ The third, and most worrying challenge, was the requirement in the NPR for the development of a new class of low-yield nuclear weapons designed to destroy hardened and deeply buried WMD facilities. STRATCOM argued that such facilities could not be effectively destroyed by conventional weapons. Nor could they be targeted with existing nuclear weapons because of the very great collateral damage that would be caused. Critics obviously worried that the whole point of such mini-nukes was to make them more useable and hence this increased the risk that they would be used one day. Indeed the US Congress outlawed research and development into nuclear warheads with a yield below 5 kilotons precisely because such ‘low-yield nuclear weapons blur the distinction between nuclear and conventional war’.Footnote ⁴⁹ However, Congressional appreciation of the threat changed following 9/11. In 2003, Congress approved funds for the development of a new 5 kiloton weapon called the Robust Nuclear Earth Penetrator (RNEP).Footnote ⁵⁰ And in 2004, Congress repelled its 1993 ban and provided funding for research into nuclear warheads below 5 kilotons.Footnote ⁵¹ In 2005, the majority view in Congress changed back to original concerns, and it halted research funding for the RNEP. But it is highly likely that the National Nuclear Security Administration will seek to repackage the programme so that it can complete its research into this weapon system.Footnote ⁵² Only this third challenge raised by the NPR is discussed by Tannenwald, who notes that were the US to develop a new generation of low-yield nuclear weapons, this would represent ‘a step backward in terms of the taboo’.Footnote ⁵³

Tannenwald does well to chart the rise of the nuclear taboo. But she seems reluctant to recognise the limits of this norm, as suggested by US military beliefs about nuclear weapons, the ambiguity in international law on nuclear use, and new civilian guidance on nuclear targeting. Tannenwald has high hopes for the nuclear taboo and that it may even lead to the grander prospect of nuclear abolition. But she fails to see that the nuclear taboo may equally decline in the post-9/11 world. Indeed, if deterrence and taboo operated in synergy to discourage American nuclear use during the Cold War, then one wonders if this synergy still exists, given that Russia is struggling to maintain its nuclear arsenal while the US continues to modernise its own strategic nuclear forces.Footnote ⁵⁴ Of course, the rise of new nuclear powers, such as Iran, may ensure that deterrence and taboo remain coupled, mutually reinforcing, and so operative.Footnote ⁵⁵ Nonetheless, the nuclear taboo may decline via two other routes. The first may occur following nuclear use. American has demonstrated remarkable restraint since 1945 but the nuclear taboo may be yet broken by some other power. Indeed, the highly militarised competition between India and Pakistan carries an ever-present risk that the conflict over Kashmir may escalate into nuclear use by one or both sides.Footnote ⁵⁶ Tannenwald suggests that any nuclear use could have devastating consequences for the taboo: ‘use of even one nuclear bomb moves one irrevocably to a new world, with the unimaginable consequences that could follow. It opens a Pandora's box’.Footnote ⁵⁷ However, even here she sees hope. She argues that the circumstances of nuclear use and how states react will determine how much damage is done to the taboo by nuclear use. Thus, nuclear use by some terrorist group (who break international norms as a matter of routine) would be more tolerable for the taboo than use by a ‘rational’ state. Equally, the taboo might even be affirmed following use of nuclear weapons, depending on how other states react. Tannenwald accepts that it would be bad news for the taboo if the state that suffered nuclear attack responded in kind. But she goes on to argue that the successful application of ‘international pressure’ to prevent nuclear retaliation would ‘affirm the taboo and the unacceptability of such weapons’.Footnote ⁵⁸ Lynn Eden's article in this forum discusses the problems underlying this optimistic line of reasoning. The second route of decline is a less dramatic one. The nuclear taboo may be replaced by a norm that is more tolerant of nuclear weapons and nuclear use. Jeffrey Lantis describes how this may occur through a process of ‘constructive norm substitution through contestation’. He points to the 2008 US-Indian nuclear deal, where the US government overturned a Congressional ban on civil nuclear cooperation with states that do not fully abide by the Nuclear Non-Proliferation Treaty regime, as illustrative of this trend.Footnote ⁵⁹ And indeed, there is analysis to suggest that for India's part, the deal represents the culmination of a process of norm replacement, with the substitution of the norm of non-alignment (which is foundational to Indian strategic culture) with a norm of strategic engagement.Footnote ⁶⁰

The prospects for the nuclear taboo may be uncertain. But the prospects for this book are not. Notwithstanding the issues raised above, this is a superb work of scholarship with vital implications for policy. Tannenwald has made a major contribution to constructivist scholarship in demonstrating that even in this most critical area of national security, norms have worked alongside the balance of power in restraining state action.Footnote ⁶¹ And in so doing she has greatly enriched our understanding of the ‘long peace’ that held between the US and Soviet Union.Footnote ⁶² The Nuclear Taboo forces IR scholars to rethink the nature of deterrence.Footnote ⁶³ Perhaps most important of all, it encourages activists and policymakers to look to the power of norms in protecting civilians from war.Footnote ⁶⁴