Tag Archive for: Nuclear Deterrence

Imagining deterrence without nuclear weapons

Nuclear deterrence, with its inherent risk of annihilation, cannot remain the bedrock of international security. Nuclear states, particularly great powers, can and should work on new conventional strategic options that can effectively deter aggression without posing an existential threat to humankind. Developing viable alternatives is necessary if we’re ever to move towards global nuclear disarmament. 

One possibility is a disarming strike—the use of strategic non-nuclear capabilities calibrated to swiftly degrade an adversary’s ability to wage offensive war. Unlike a nuclear counterforce strike, which would involve a pre–emptive nuclear attack against an enemy’s nuclear arsenal, a disarming strike would rely on conventional and cyber capabilities to target critical military systems and infrastructure. It would hold at risk the key sinews of enemy military power—leadership, communications, logistics and major war–fighting systems—through a combination of massive cyberattacks, electromagnetic pulse weapons and other conventional capabilities. The goal would be to deter aggression by threatening to render a significant portion of the enemy’s military machine inoperable, rather than by threatening massive loss of life. 

The increasing integration of artificial intelligence into defence capabilities can exponentially increase the accuracy, speed and power of non-nuclear disarming strikes, thereby strengthening their deterrence potential. AI-powered systems can process vast amounts of real-time data from a wide array of sensors and intelligence sources to identify, track and target an adversary’s critical military assets with unprecedented precision. They can optimise the timing and coordination of strikes to maximise their disruptive impact on the enemy while minimising collateral damage. For example, swarms of AI-guided drones and missiles could autonomously locate and neutralise an adversary’s key leadership nodes, communication hubs, supply lines and offensive forces in a matter of minutes. The prospect of having its military infrastructure paralysed before it could even launch an attack would give any aggressor serious pause. 

Furthermore, AI-enhanced systems can ensure the robustness of second-strike capabilities by making them more resilient, dispersed and autonomous. AI could enable a dense, multi-layered web of early–warning sensors and interceptors to shoot down incoming missiles. Drone swarms and uncrewed vehicles could be pre-deployed in hidden locations, guided by AI to survive initial attacks and retaliate when ordered. With AI, states could credibly threaten precise, certain and devastating retaliation to aggression without necessarily revealing the full scope of their capabilities in advance. 

If harnessed responsibly and effectively, AI has the potential to bolster strategic stability by ushering in a new era of ‘mutually assured debilitation’. By convincingly holding each side’s military infrastructure at risk of severe debilitation while being less destructive and more discriminating than nuclear bombs, AI-driven non-nuclear deterrence could prove to be a compelling alternative to the grim doctrine of nuclear MAD. The knowledge that an adversary possesses AI-empowered, always-ready counterstrike abilities that can’t be easily discovered and neutralised would significantly enhance deterrence, reducing the temptation for pre–emptive attacks or provocations. It may offer a viable path for nuclear powers to eventually move away from relying on doomsday weapon systems for their security, making the world a safer place. 

This vision of AI-driven non-nuclear deterrence is not without its potential pitfalls. An increasing reliance on AI and complex cyber capabilities introduces new vulnerabilities, including susceptibility to hacking, algorithmic biases and unforeseen errors in autonomous decision-making processes. Such systems could potentially lower the threshold for conflict initiation, as some states could possibly engage in cyberwarfare and strategic strikes with less forethought than they would otherwise with nuclear weapons. The ambiguity in international law concerning cyberattacks and AI warfare complicates matters, potentially leading to miscalculations or unintended escalations. Additionally, there remains the moral quandary of increasingly automated warfare in which the human element is progressively distanced from the act of war, potentially eroding accountability. 

Despite those concerns, it remains a moral and strategic imperative to explore alternatives to nuclear deterrence. The current war in Ukraine has included an unsettling number of nuclear threats, echoing the hair-trigger tensions of the past. More concerningly, recent war-gaming scenarios suggest that AI systems are likely to resort to nuclear escalation in a crisis. Even if nuclear deterrence has historically prevented great–power war, its infallibility for the future is not a given. A single misstep could destroy the entire human race. The world has come close to the brink at least twice, first during the 1962 Cuban missile crisis, then during NATO’s 1983 Able Archer exercise. For the sake of humanity, we must put the nuclear genie back into its bottle. That will require us to imagine credible alternative forms of deterrence.

Is nuclear war inevitable?

Russia’s invasion of Ukraine and nuclear sabre rattling against the West have revived a debate about nuclear weapons. Last year, when a United Nations treaty to ban such weapons outright entered into force, none of the world’s nine nuclear-weapon states was among the 86 signatories. How can these states justify possessing weapons that put all of humanity at risk?

That is a pertinent question, but it must be considered alongside another one: if the United States were to sign the treaty and destroy its own arsenal, would it still be able to deter further Russian aggression in Europe? If the answer is no, one also must consider whether nuclear war is inevitable.

It’s not a new question. In 1960, the British scientist and novelist C.P. Snow concluded that nuclear war within a decade was ‘a mathematical certainty’. That may have been an exaggeration, but many believed Snow’s prediction would be justified if a war occurred within a century. In the 1980s, Nuclear Freeze campaigners like Helen Caldicott echoed Snow in warning that the build-up of nuclear weapons ‘will make nuclear war a mathematical certainty’’

Those advocating the abolition of nuclear weapons often note that if you flip a coin once, the chance of getting heads is 50%; but if you flip it 10 times, the chance of getting heads at least once rises to 99.9%. A 1% chance of nuclear war in the next 40 years becomes 99% after 8,000 years. Sooner or later, the odds will turn against us. Even if we cut the risks by half every year, we can never get to zero.

But the coin-flip metaphor is misleading where nuclear weapons are concerned because it assumes independent probabilities, whereas human interactions are more like loaded dice. What happens on one flip can change the odds on the next flip. There was a lower probability of nuclear war in 1963, just after the Cuban missile crisis, precisely because there had been a higher probability in 1962. The simple form of the law of averages doesn’t necessarily apply to complex human interactions. In principle, the right human choices can reduce probabilities.

The likelihood of nuclear war rests on both independent and interdependent probabilities. A purely accidental war might fit the model of the coin flip, but such wars are rare, and any accidents might turn out to be limited. Moreover, if an accidental conflict remains limited, it may trigger future actions that further limit the probability of a larger war. And the longer the period, the greater the chance that things may have changed. In 8,000 years, humans may have much more pressing concerns than nuclear war.

We simply don’t know what the interdependent probabilities are. But if we base our analysis on post–World War II history, we can assume that the annual probability isn’t in the higher range of the distribution.

During the Cuban missile crisis, US President John F. Kennedy reportedly estimated the probability of nuclear war to be between 33% and 50%. But this didn’t necessarily mean unlimited nuclear war. In interviews with participants in that episode on its 25th anniversary, we learned that, despite the massive superiority of the US nuclear arsenal, Kennedy was deterred by even the slightest prospect of nuclear war. And the outcome was hardly an unalloyed American victory; it involved a compromise that included the quiet removal of US missiles from Turkey.

Some people have used the mathematical-inevitability argument to push for unilateral nuclear disarmament. Inverting the Cold War slogan, future generations would be better off red than dead. But nuclear knowledge cannot be abolished, and coordinating abolition among nine or more ideologically diverse nuclear-weapon states would be extremely difficult, to say the least. Unreciprocated unilateral steps could embolden aggressors, increasing the odds of an unhappy endgame.

We have no idea what utility and risk acceptance will mean to distant future generations, or what people will value in 8,000 years. While our moral obligation to them compels us to treat survival very carefully, that task doesn’t require the complete absence of risk. We owe future generations roughly equal access to important values, and that includes equal chances of survival. That’s different from trying to aggregate the interests of centuries of unknown people into some unknowable sum in the present. Risk will always be an unavoidable component of human life.

Nuclear deterrence is based on a usability paradox. If the weapons are totally unusable, they don’t deter. But if they are too usable, nuclear war with all its devastation might occur. Given the usability paradox and the interdependent probabilities related to human interactions, we cannot seek an absolute answer to what constitutes ‘just deterrence’’ Nuclear deterrence is not all right or all wrong. Our acceptance of deterrence must be conditional.

The just war tradition that we have inherited over the centuries suggests three relevant conditions that must be met: a just and proportionate cause, limits on means, and prudent consideration of all consequences. I derive five nuclear maxims from these conditions. In terms of motives, we must understand that self-defence is a just but limited cause. As for means, we must never treat nuclear weapons as normal weapons, and we must minimise harm to innocent people. And regarding consequences, we should reduce the risks of nuclear war in the near term and try to reduce our reliance on nuclear weapons over time. A bomb in the basement involves some risk, but not as much risk as bombs on the front lines.

The war in Ukraine has reminded us that there is no way to avoid uncertainty and risk. The goal of reducing (not abolishing) the role of nuclear weapons over time remains as important as ever. Richard Garwin, the designer of the first hydrogen bomb, calculated that, ‘If the probability of nuclear war this year is 1%, and if each year we manage to reduce it to only 80% of what it was the previous year, then the cumulative probability of nuclear war for all time will be 5%.’ We can live moral lives with that probability.

Would the US nuclear umbrella have protected Ukraine from Putin?

Russia’s invasion of Ukraine has revived many questions about nuclear deterrence. Whatever the outcome of what could be a long war, the issues it has raised won’t go away.

In 1994, Ukraine surrendered the nuclear weapons it had inherited from the Soviet Union in return for security guarantees from the United States, the United Kingdom and Russia. But those guarantees turned out to be worthless, and because Ukraine isn’t a member of NATO, it’s not covered by the extended deterrence of the US nuclear umbrella.

What about the former Soviet republics that have joined NATO? Would US extended deterrence actually work for Estonia, Latvia and Lithuania, or for America’s allies in Asia? For deterrence to be credible, nuclear weapons must be usable. But if they are too usable, an accident or misjudgement could easily lead to a disastrous nuclear war.

To achieve an effective balance, we must consider the appropriate mix of nuclear, conventional and other instruments, and then reduce the nuclear component whenever possible. For example, whatever the appropriate response to North Korea’s growing nuclear arsenal may be, it shouldn’t include a reintroduction of the tactical nuclear weapons that President George H.W. Bush removed from the Korean peninsula in 1991.

Similarly, for Japan, the credibility of US extended deterrence hinges on the stationing of American troops there, not on the presence of nuclear weapons. By sharing the vulnerability that Japanese troops face, the US establishes a community of fate that reduces its allies’ fear of abandonment. While sceptics used to point out that the small contingent of US troops in Berlin couldn’t possibly defend that city against the Soviet Union, America’s physical presence nonetheless proved to be essential to deterrence and a peaceful outcome to the Cold War. (There was also a time when the US had nuclear artillery stationed in Europe; however, because of the risks to command and control, it was removed.)

As the US and other countries have continued to modernise their forces, the usability debate has persisted. Deterrence depends on psychology, and some analysts argue that perceived superiority in usable weapons can make a difference during crises. Others, like the late Columbia University political scientist Robert Jervis, argue that all measures of nuclear balance are too crude to be useful in reaching such conclusions. Mutual assured destruction is a condition, not a policy.

In fact, history has shown that one doesn’t need a high probability of use to create existential deterrence. Despite the overwhelming superiority of America’s nuclear arsenal, President John F. Kennedy still felt deterred by even a small risk of escalation during the Cuban missile crisis. Today, small, accurate nuclear weapons seem so usable that we have come to treat them as normal. But the dangers of escalation remain, and the location of some military targets near cities means the dangers will persist. Avoiding catastrophe depends more on reducing the risks of nuclear war—both deliberate and inadvertent—than on changes in targeting doctrines.

Following a risk-reduction maxim, we can reject some policies outright. For example, a launch-on-warning protocol delegating nuclear launch authority to battlefield commanders may enhance deterrence, but it also raises the risk of unnecessary provocation. Defence hawks sometimes forget that deterrence depends on the opponent’s psychology, not just their own.

On the other hand, defence doves’ proposals to escape the usability dilemma and appease adversaries may create an impression of weakness, thereby tempting adversaries to take more risks. Dovish nuclear strategists are sometimes too clever by half when they devise elaborate strategies based solely on calculations rather than on experience.

Representing a middle ground between hawks and doves, defence owls place a premium on risk reduction. Whereas hawks have a hair trigger and doves have a sticky holster, owls offer a reliable safety catch.

Russia’s invasion of Ukraine reminds us that we are still living in a world with nuclear weapons, and that we should be endeavouring to reduce (though not abolish) stockpiles over the long run. As the physicist Richard Garwin once noted, ‘If the probability of nuclear war this year is one percent, and if we manage each year to reduce the probability to only 80 percent of what it was the previous year, then the cumulative probability of nuclear war for all time will be 5 percent.’

The psychological effect of nuclear deterrence on our moral lives is another significant long-term consequence to consider. The theologian Paul Ramsey once likened nuclear deterrence to tying babies to the bumpers of cars as a means of slowing traffic and reducing the number of lives lost to road accidents. But while that metaphor helps incite moral repugnance, it’s not an accurate depiction, because people today simply don’t suffer from the kind of anxiety that one would expect to see in Ramsey’s scenario. A lack of anxiety doesn’t warrant complacency, of course; rather, it vindicates ‘just deterrence’ (an extension of just war theory), combined with a long-term focus on reducing nuclear risk.

Although any effort to predict long-term change will almost certainly be frustrated, we can still sketch rough outlines of plausible future scenarios, while always remaining prepared for surprises—both technological and political. In the past, technological improvements in accuracy made it possible to reduce the yield and volume of nuclear weapons. However, a whole new set of problems has come with the rise of cyberattacks on command-and-control systems, laser attacks on satellites, and autonomous weapon systems. These are the types of risks that we must seek to anticipate, understand and reduce.

Politics, too, will change. During the Cold War, the ideological antagonists slowly developed a regime of tacit and explicit rules of the road, because each recognised that it had an interest in avoiding nuclear war. Today’s strategic competition with China and Russia could take any number of turns in the future. As we adjust to changes and surprises, we must continue to consider how our decisions will affect the long-term goal of reducing the risk of nuclear war.

The path from nuclear prohibition to disarmament

On the 76th anniversary of the atomic bombings of Hiroshima and Nagasaki, for the first time, a global treaty is in force outlawing the bomb. Last month, I completed and dispatched to the publisher an edited book on the nuclear ban treaty (or the Treaty on the Prohibition of Nuclear Weapons, as it’s officially called) with contributions from many familiar people in academia, think tanks, foreign ministries and civil society. A number of recurrent themes run through the 32 chapters.

Not one author questions that the Non-Proliferation Treaty has been a critical pillar of the international security architecture for half a century. There would be seriously damaging consequences were it to collapse. That said, doubts are increasing as to whether the NPT has reached the limits of its potential for advancing the cause of nuclear disarmament. This explains why, despite its proven resilience, the NPT is facing unprecedented pressure. If the possessor and umbrella states are not prepared to give up nuclear weapons, what have the non-nuclear-weapon states got to lose by withdrawing from the NPT? Perhaps more pressingly, is the threat of withdrawal their one remaining effective piece of leverage over the policies of the nuclear-armed states?

Regardless of what one thinks of the NPT’s historical record in underpinning strategic stability, in recent years nuclear risks have grown with heightened geopolitical tensions, additional roles for nuclear weapons, blurred boundaries between nuclear and precision conventional munitions, and expanding frontiers in space, cyber and AI technologies. Moreover, the transformation of the Cold War–era nuclear dyad into interlinked nuclear chains, some of them in geographical theatres of contiguous nuclear-armed rivals, diminishes the relevance of the traditional approaches to managing strategic stability among nuclear-armed states, not to mention the added risks from non-state actors.

As Sverre Lodgaard from the Norwegian Institute of International Affairs puts it: ‘The NPT is in miserable shape, betrayed on the disarmament dimension, stuck in the Middle East and mostly irrelevant to the Asian nuclear-armed states.’

An important motivation for the ban treaty was the stubborn refusal of the five nuclear-weapon states to act on their NPT Article 6 commitment to nuclear disarmament. This background reality is indispensable for understanding the mounting frustrations among the NPT non-nuclear states that gradually turned into anger and a determination to seize control of the nuclear disarmament agenda. The NPT was gravely weakened by this lacklustre implementation of Article 6 and the ban treaty’s new normative standard is an effort to redress the weakness and strengthen the NPT.

Reframing the debate from disarmament as a security issue into a pressing humanitarian concern was critical to the successful conclusion of negotiations. The old paradigm had proven unable to break through what Austrian diplomat Alexander Kmentt calls ‘the wall of the nuclear deterrence dogma’. The reframing of a traditional security debate into a humanitarian discourse had an important precedent in the Ottawa Treaty that banned anti-personnel landmines. An equally important feature of the Ottawa Treaty was the role of a state champion in the carriage of state–civil society partnership to successful conclusion at an international conference or summit.

Thus, the International Campaign to Abolish Nuclear Weapons was to the ban treaty what the International Campaign to Ban Landmines was to the Ottawa Treaty in forging a global coalition of civil society groups and like-minded states. This also facilitated a democratic shift in the nuclear debate, with non-nuclear-weapon states using the UN General Assembly, the central democratic body of the international system, as the site and forum of negotiations and adoption.

The ban treaty impacts those non-nuclear states that have relied on the nuclear-deterrence-based security architecture of the alliance leader’s nuclear weapons. The NPT had camouflaged the underlying hypocrisy of many states in pretending to support nuclear disarmament—just not yet, like St Augustine’s plea on chastity—while hosting nuclear weapons, relying on nuclear deterrence for national security and sheltering under the nuclear umbrella of allies. Yet there’s no legal incompatibility between the ban treaty and the NPT. While the NPT had enabled the umbrella states to fudge the tensions between membership of a nuclear alliance and commitment to nuclear disarmament, the ban treaty has compelled them to confront the hypocrisy head on. This might well explain the ferocity of their opposition: it shows the mirror of their disingenuousness to their own citizenry and they don’t like it.

The nuclear-armed states and umbrella allies have effectively formed a mutual support group that justifies possession of the bomb by pointing to the demands for nuclear-deterrence-based security from the allies. The ban treaty forces the issue: do the nuclear-dependent states intend to continue to shelter under the nuclear umbrella or start behaving like non-nuclear states? In other words, the treaty has the potential to embarrass umbrella states by reopening fundamental domestic debates on the role of nuclear weapons and deterrence strategies. At the same time, says former Canadian disarmament ambassador Paul Meyer, ‘To fold the metaphorical “nuclear umbrella” it will be necessary to convince those sheltering under it that it is safe to come out and to recognise that the umbrella may be more of a danger than a protection’—a nuclear lightning rod more than a repellent.

Former UN under-secretary-general for disarmament Angela Kane argues that the ban treaty has converted a longstanding political aspiration into a legal framework. But the legal obligations of the treaty can’t apply to non-signatories, and the possession of nuclear weapons by nine states didn’t suddenly became illegal with the treaty’s entry into force on 22 January 2021. Equally, however, the claim that a UN-negotiated treaty, following a UN-authorised process and conference, has no implications for the legality and legitimacy of nuclear-weapon possession and practices is also implausible.

Non-signatory possessor states may be placing themselves ‘outside the law’ and the balance of incentives and disincentives for states, individuals and companies has been recalibrated. Punitive consequences could follow in due course, says Joelien Pretorius from South Africa’s University of the Western Cape, if patterns of practice and expectations evolve to give the prohibition the status of customary international law.

Editors’ picks for 2020: ‘The role of nuclear weapons in China’s national defence’

Originally published 27 May 2020.

At the end of April, two upgraded Chinese Type-094 nuclear-powered ballistic missile submarines (SSBNs) reportedly went into service. But China’s SSBN capability is a far less important component of its nuclear deterrent than its land-based missile force. And that nuclear deterrent plays an important but limited role in China’s national defence. Absent major strategic change, the role of nuclear weapons in China’s national defence strategy is unlikely to expand. And absent major technological change, the relative importance of China’s sea-based deterrent is also unlikely to grow.

Although the commander of US Strategic Command, Admiral Charles A. Richard, recently stated that he could ‘drive a truck through China’s nuclear no first use policy’, that policy has played a critical role in China’s nuclear force development since 1964. China’s nuclear force structure is optimised to ride out an adversary’s nuclear strike and then retaliate against an adversary’s strategic targets, rather than credibly threaten first use. China’s operational doctrine for its nuclear forces doesn’t include plans for the first use, or threat of first use, of nuclear weapons in a conventional conflict. While Chinese leaders and strategists have debated changes to the no-first-use policy from time to time, there’s no sign that China plans to abandon it. The policy was most recently reaffirmed in China’s 2019 defence white paper.

China’s top leaders in the politburo and Central Military Commission exercise strict control over both the formulation of nuclear strategy and the authority to alert or use nuclear weapons. To ensure they’re not used accidentally, mistakenly or without authorisation, nuclear weapons are kept off alert in peacetime and warheads are stored separately from delivery systems in a central depot deep in the country’s interior.

There are two potential changes to the threat environment that could prompt Beijing to rethink its restrained nuclear posture: a dramatic increase in the intensity of the US threat China faces and a radical technological change that weakens its retaliatory-only policy.

If Chinese leaders concluded that a future conflict with the US posed an existential threat rather than a limited war, they could look to nuclear weapons as insurance against a conventional defeat that eliminated the Chinese state. But such a change is by no means a given. Chinese strategists stress a number of reasons for the country’s restrained nuclear strategy, including the difficulty of controlling nuclear escalation and geography. China’s large size provides it with non-nuclear options for defeating a conventional military threatening its survival. An increase in US hostility wouldn’t remove these incentives for restraint.

A breakthrough in the development of counterforce technology is also unlikely to change China’s retaliatory nuclear posture, unless it were so radical that it made that posture unviable. Those changes would have to enable the US to credibly threaten to destroy most of China’s retaliatory force. It would also have to render China’s other options for ensuring a survivable nuclear force futile, such as expanding its arsenal size or shifting to a launch-on-warning alert status. Such radical technological change is unlikely, despite persistent US efforts to improve its counterforce capabilities.

Regardless of whether either of these situations come to pass, China’s land-based missile force is unlikely to be displaced by its sea-based deterrent as the primary leg of its retaliatory nuclear capability, for four reasons.

First, Chinese strategists acknowledge the shortcomings of the current generation of Type-094 submarines, which are noisy and therefore vulnerable to sophisticated US strategic anti-submarine warfare (ASW) capabilities. China could overcome these technological hurdles in the future, although it would be racing against simultaneous American ASW improvements—something the US has proven adept at throughout and since the Cold War.

Second, and regardless of its technological progress, China does not (yet) appear to have invested in its own strategic ASW forces. It may therefore lack confidence that SSBNs patrolling in the open ocean could evade detection by US ASW capabilities. Protecting SSBNs using the PLA Navy’s conventional forces is another option, but would come at an opportunity cost for other naval missions.

Third, China’s geography makes its SSBNs more vulnerable to ASW than those of the US and other naval nuclear powers because they must pass through chokepoints in the first island chain to enter the Western Pacific. The territory bordering those chokepoints belongs to US allies and partners, who may assist US ASW with shore-based signals processing. No technical improvements to Chinese submarines are likely to be able to overcome the disadvantages posed by its geography.

Fourth, developing operational doctrine for SSBNs poses distinctive challenges to strict control of top Chinese leaders over the use of nuclear weapons. Those leaders may not be comfortable with pre-delegating authority to use nuclear weapons to submarine commanders if communications are severed, or mating nuclear warheads and missiles in peacetime. Yet without these two amendments to its nuclear operations, which is optimised for the land-based force, China may not be able to reap the full benefits of deploying an SSBN force for securing a second-strike capability.

Given these constraints, why, then, has China continued to develop a sea-based nuclear deterrent?

Speculatively, a mix of hedging and organisational interests of the PLA Navy is the most likely explanation. SSBNs may help China to hedge against improvements in US missile defence focused on intercepting missiles launched from the Chinese mainland.

Although China’s SSBN force is unlikely to become central to securing its second-strike capability, it could have a strong influence on US–China strategic stability.

In addition to the use-or-lose pressures resulting from operating a vulnerable SSBN force in a crisis, SSBNs could undermine confidence in China’s nuclear restraint. If Chinese leaders decide to change their warhead handling practices, or pre-delegate nuclear launch authority, they will change longstanding practices for China’s nuclear operations. As China formulates operational doctrine for its SSBN force, it should carefully consider the value of existing nuclear practices as signals of restraint.

This piece was produced as part of the Indo-Pacific Strategy: Undersea Deterrence Project, undertaken by the ANU National Security College. This article is a shortened version of chapter 7, ‘The role of nuclear weapons in China’s national defence’, as published in the 2020 edited volume The future of the undersea deterrent: a global survey. Support for this project was provided by a grant from Carnegie Corporation of New York.

A ‘P5+4’ summit could break the nuclear deadlock

In April, US President Donald Trump directed White House officials to identify pathways to new arms control agreements with Russia and China. If he’s looking for a big and bold new idea, here’s one: a ‘P5+4’ nuclear summit of the leaders of the nine countries that have the bomb.

The five permanent members of the UN Security Council (the ‘P5’) are the only countries recognised by the Nuclear Non-proliferation Treaty (NPT) as lawful possessors of nuclear weapons: China, France, Russia, the UK and the US. The ‘+4’ are the non-NPT nuclear-armed countries—India, Israel and Pakistan—and North Korea, the world’s only NPT defector state.

The existing architecture of nuclear arms control has served us well but is now crumbling. It was weakened first by the US exit from the Anti-Ballistic Missile Treaty in 2002 and then the indefinite delay of the entry into force of the Comprehensive Test-Ban Treaty. More recently, the deterioration has accelerated with the Trump administration’s abandonment of the nuclear deal with Iran, the US and Russian suspensions of the Intermediate-Range Nuclear Forces Treaty, and the failure thus far to discuss extending New START beyond its expiry date of 2021.

There is a related problem. The NPT-centric architecture cannot accommodate the reality of four non-NPT possessor states. The architecture deficit is exacerbated by the fact that the agenda of nuclear arms control, non-proliferation and disarmament has stalled. The Korean denuclearisation-cum-peace-process has run out of steam. Last month’s meeting of the preparatory committee for the 2020 NPT review conference could not reach agreement on a common statement.

In 2017, two-thirds of the international community adopted the UN Treaty on the Prohibition of Nuclear Weapons. All nine bomb-possessing countries, and about 30 nuclear-dependent allies including Australia, mock this as empty virtue-signalling by those who don’t have the bomb. Yet nuclear powers themselves invite ridicule by insisting that the only proper forum for engaging in arms control negotiations is the Conference on Disarmament in Geneva. This farcical body has not managed to agree on its own work agenda for over 20 years.

The primary motivations behind the Nuclear Ban Treaty were heightened consciousness of elevated levels of nuclear risks and threats, exasperation at the refusal of the nuclear-armed states to engage in credible disarmament negotiations, and frustration with the fraying arms control architecture. The primary impact of the treaty won’t be operational but normative: it attaches a moral stigma to continued possession and to doctrines of deterrence.

So the existing international machinery is no longer fit for purpose even for individual items on the nuclear agenda, let alone all of them. Summit diplomacy could be a mechanism for cutting through the Gordian knot of global gridlock.

Not all summits are successful and not all topics lend themselves well to summit diplomacy. Summits make the most difference in tackling those global problems where leadership commitment is the critical missing variable, where the chief obstacle to identifying policy convergence and reaching consensus on next steps is the lack of an appropriate forum, and where speedy resolution is essential.

The nuclear security summits convened during Barack Obama’s time as president, for example, consolidated and strengthened the disparate national, multilateral and cooperative institutions and instruments to ensure nuclear security and prevent nuclear smuggling. They were important for having clear US presidential leadership on this critical area of the nuclear challenge and elevated the issue to the level of a global leaders’ summit.

Nuclear arms control satisfies all the key criteria for a summit. Like pandemics, climate change and biodiversity, nuclear threats spill across national boundaries and defy unilateral solutions. A summit of the nine political leaders, but only them, that is appropriately structured and has been adequately prepared can focus them to do what they alone can do—make tough choices from among competing interests and priorities. Cabinet ministers have single portfolio responsibilities. Heads of state and government have to oversee the entire agenda. With broad, overarching responsibilities, leaders can weigh priorities and balance interests across competing goals, sectors, and national and international objectives.

Before a summit, leaders’ engagement catalyses officials to focus on and resolve interagency differences, jurisdictional turf battles and veto points. At the summit, leaders’ involvement makes it possible for states to bargain across issues in order to cut deals; that is, to trade apples for oranges. After the summit, their commitment to the agenda invests it with legitimacy and prioritises its implementation and can help to redirect resources even amid constrained budgetary environments.

The first thing a nuclear summit should do is reaffirm the famous 1987 declaration by US President Ronald Reagan and Soviet leader Mikhail Gorbachev: ‘a nuclear war cannot be won and must never be fought’. If all nine leaders sign such a statement, it can be adopted as a resolution also by the UN Security Council and General Assembly. That would reverse the recent trend to normalise the discourse of possible nuclear-weapon use and, by hardening the normative boundary between nuclear and other weapons, perhaps also help to stop mission creep with respect to the roles and functions of nuclear weapons.

Other items on the agenda could include drafting a declaration, to be duly converted into a global convention, on no first use of nuclear weapons by any country; taking nuclear weapons off high-alert launch status as a crisis stability measure (around 2,000 nuclear warheads are currently on high alert); securing verified reductions in warhead numbers by Russia and the US, which account for over 90% of global stockpiles; and determining how best to transition from US–Russian agreements to those involving all nuclear powers. At the same time, regional rivals could explore bilateral risk-reduction arrangements on the sidelines of the global summit.

A summit-level agreement on a few important items would be a powerful stimulus to restarting stalled talks on other outstanding items like bringing the Comprehensive Nuclear-Test-Ban Treaty into force and commencing negotiations on a fissile materials cut-off treaty. Even a modestly successful summit would tell the world that the nine powers take seriously their responsibility for preserving nuclear peace. If Trump takes the initiative and assumes ownership of the summit, he would be more deserving of the Nobel Peace Prize than Obama in 2009.

Deterrence debate ignores the hard questions about nuclear war

Andrew Davies and Rod Lyon have had an interesting debate here recently about nuclear weapons. Andrew has argued that we need to take the risk of nuclear war more seriously and that we should therefore work much harder to eliminate nuclear weapons. Rod sees the risk of nuclear war as very low, and argues that eliminating nuclear weapons would make the world more dangerous by making major conventional war more likely.

I’d like to triangulate their debate by supporting Andrew’s pessimism over Rod’s optimism about the risk of nuclear war, but offering a rather different view from Andrew’s of what we should do about it.

Rod argues that nuclear war is unlikely, and that nuclear weapons prevent major conventional wars, by extrapolating from the experience of the 73 years since nuclear weapons appeared. There’s something in what he says. It’s plainly true that since 1945 nuclear weapons have not been used, and that there have been no full-scale major-power wars, and it’s very probable that the existence of nuclear forces has helped prevent major wars from breaking out.

The question is how far we can credibly extrapolate from that. My problem with Rod’s analysis is that when he concludes on this basis that nuclear weapons prevent war, his sample size is too small. The most you can say is that they have prevented war so far, but almost all our data comes from one particular historical episode—the Cold War, the only full-scale hegemonic rivalry we’ve seen since 1945.

And as Rod himself says in his response to Andrew, every strategic contest is different and unique. The Cold War certainly was: its progress and outcome reflected the very specific strategic, ideological, geographic, economic, military and internal political characteristics of the rivals and their rivalry, and the skills and experience of those who made the big decisions on both sides.

In those specific circumstances, nuclear weapons appear to have prevented major war. In particular, it seems to me that that was because the circumstances of the Cold War created a situation in which each side was convinced that the other was resolved to fight a nuclear war, despite the catastrophic consequences, in order to prevent any significant shift in the other’s favour. Deterrence worked in the Cold War because both sides believed—or, to be more precise, believed enough—that the other wasn’t bluffing.

I’d share Rod’s optimism that nuclear weapons will keep on keeping the peace for as long as that is true. But how sure can we be that this will be so in future large-scale strategic contests between nuclear powers? And even more urgently, how sure can we be that this is true in the contests we see today?

The risk of nuclear war between, say, the US and China is not that either side will decide that it’s worth fighting one to achieve their strategic goals. The risk is that they will convince themselves that the other side is not willing to fight one to stop them, and they will turn out to be wrong.

How likely is that? How likely is it, for example, that China would come to believe that America would not fight a nuclear war to defend Taiwan? How likely is it that Washington today can display the statecraft required to convince Beijing that it would, or even understand what is required to convince China of its resolve?

I think these likelihoods are very low, in part because of the almost universal assumption in Washington that China could not possibly doubt America’s resolve in Asia. This is dangerously complacent, when the US has done so little to demonstrate that resolve, and provided so many good reasons for Beijing to doubt it. That makes the risk of nuclear war between America and China really quite high.

So what should we do about it? Andrew thinks we should redouble our efforts to eliminate nuclear weapons. I certainly agree that that would be a great thing to do, but it seems a very inadequate response to the risks we face today. After all, there’s no reason for confidence that nuclear weapons will be eliminated anytime soon.

That being so, we should focus on the more modest but more achievable task of trying to reduce the risk that nuclear weapons are used. And how could we do that? There seem to be only two sure ways.

The first would be to establish the clarity of resolve that underpinned successful nuclear deterrence in the Cold War. That’s harder for America than for China, but it wouldn’t be impossible. It must, however, be real, because bluffing is almost bound to fail. That means Americans must first debate and decide whether they really are willing to fight a nuclear war and risk losing cities to save Taiwan. The answer is most probably ‘no’.

The second would be to step back from the strategic contest that is now escalating between Washington and Beijing. Those who share Rod’s confidence that nuclear weapons prevent major war and will therefore never be used in combat aren’t much worried about increasing competition between nuclear powers, because they are sure it won’t lead to war, or that if war comes it won’t become nuclear. They are therefore less uneasy about escalating strategic rivalry, and more inclined to oppose policies that aim to prevent or limit it.

Those who, like me, see a real risk that rivalry between great powers leads to war, and that war between nuclear-armed powers can easily go nuclear, tend to place a higher priority on limiting rivalry, even at the price of making concessions that we would otherwise be very reluctant to make. Because, after all, we have to ask what is so important that we would be willing to fight a nuclear war to avoid it.

That’s a hard question, and it’s understandable that so many people prefer to ignore it in favour of debating the much easier one about whether nuclear weapons should be abolished.

In defence of nuclear deterrence

I read with interest the recent Strategist posts (here and here) written by my former colleague Andrew Davies, outlining his conversion to the anti-nuclear cause. Andrew’s views are always worth listening to, but on this occasion I’ll beg to differ with his conclusions.

Andrew, having read Daniel Ellsberg’s recent book on nuclear command and control, worries that we’re running an unacceptable risk of a nuclear war that occurs by accident. Moreover, he’s concerned that such an accident might well bring civilisation to an end. He reinforces that point by his reference to the dark silence emanating from our cosmic neighbours, a silence consistent with a possibly similar tale of self-extermination by industrialised intelligent life elsewhere in the cosmos. And he draws his argument to a close with a brief look at Lewis Richardson’s statistics on the frequency of war, arguing that wars are ‘randomly distributed accidents’.

Let’s start with command and control. Yes, history contains some hairy moments—that’s been relatively well known for some time, and well rehearsed recently by Eric Schlosser, as well as Ellsberg. But experience is a learning curve, not just a litany of errors. We try to fix problems, and to design systems that are less susceptible to failure.

Over time, the nuclear- weapon states have learned to manage command and control problems somewhat better than they have done in the past. Weapon security has been improved through better locks on warheads, and weapon safety improved by better design, including use of insensitive high explosives. Even attack assessment has been improved: as I understand it, two independent sources, relying on two different physical principles, are now required to verify that a nuclear attack on the US is underway. (Readers seeking a quick description of current US command and control arrangements might like to browse this overview of the latest Nuclear matters handbook.)

Let me say something too about the spectacular silence of our galactic neighbours. Frankly, I’m wary of blind speculation. As any science fiction fan knows, there are a host of reasons that might cause civilisations to end abruptly. (See, for example, Cixin Liu’s The three-body problem.)

Moreover, right here on earth, we have our own collection of ancient cities covered by jungle. Civilisations are fragile, impermanent things. History is not one long, slow trudge from darkness to enlightenment, but the rise and fall of a procession of complex societies.

Still, Andrew’s right that a large-scale nuclear war could constitute one form of civilisation-ending event. So, what should we be doing with our nuclear arsenals? For better or worse, nuclear weapons sit at the heart of the current international security order. Yes, only about 25% of states rely on nuclear weapons for their security. But look further up the power ladder. All five of the permanent members of the UN Security Council are nuclear-weapon states. All of the G7 countries (Canada, France, Germany, Italy, Japan, the UK and the US) are either nuclear-weapon states or beneficiaries of extended nuclear deterrence. Of the G20, Argentina, Brazil, Indonesia, Mexico, Saudi Arabia, South Africa and the EU don’t rely on nuclear weapons (although some have flirted with the option in the past or do so today); the other 13 (roughly two-thirds) do. Of the five BRICS countries, Brazil and South Africa are non-nuclear powers and Russia, China and India nuclear ones. In short, among the powerful, the protection afforded by nuclear deterrence is ‘normal’.

Now we’re approaching the key question: do nuclear weapons make a positive contribution to international security? Personally, I believe that nuclear weapons deter major war, and—moreover—encourage caution in policymaking. Never having read Richardson’s statistical analysis, I’m not well placed to dispute Andrew’s summary of his conclusions. But his dataset ends in 1950, only five years after the birth of the atomic age, so he certainly isn’t testing nuclear deterrence.

I’m attracted too by the recent observations of Kori Schake in her review of Lawrence Freedman’s latest book that quantitative analyses of conflict aren’t especially helpful. Freedman and Schake argue that ‘interstate wars are both rare and their circumstances particular … In reality, each interstate war is utterly unique, thus n can never be greater than one.’

Indeed, since war is really about politics and societies, we should be wary of abstracting war from its context. In that regard, it’s important to remember the world before nuclear weapons. We have only one model of industrial-age warfare devoid of the sobering effects of nuclear weapons, and it was the one which prevailed between the American civil-war years and 1945. With the industrial revolution, war’s centre of gravity moved away from the battlefield and towards national industrial capacity. Wars became uncapped contests in national endurance. People died in the tens of millions.

Nuclear weapons brought to an end that picture of warfare as a contest in industrial mass-production. In one sense, of course, they did so because they represented the zenith of the destruction-based model of war—and so inspired a set of mechanisms (such as the UN Security Council) and doctrines (such as deterrence) intended to help prevent war between the major powers. Nuclear weapons helped force a possible hot war to become a cold one, and pushed warfare itself towards contests that would be limited in magnitude and duration.

That vision of nuclear weapons is often missing in today’s debates. Around the world, evidence mounts of a nuclear order in flux. At the top level, relations between the great powers are far from ideal. Arms control agreements are under pressure, and modernisation programs are threatening to pull the future nuclear competition in new directions. Then there’s North Korea, and the special problems that it creates.

On the broad issue of assurance, things aren’t much better. President Donald Trump has seriously devalued the coinage of US extended nuclear deterrence. That’s worrying, because it bodes ill for the current non-proliferation regime.

Still, those challenges don’t invalidate the notion of deterrence, which is, after all, a doctrine that attempts to minimise actual use. But they do require us to ensure that deterrence remains effective in a shifting strategic environment. Deterrence is not without its problems—it’s merely the defence doctrine of choice for a competitive, heavily armed world. Is it going to save us from all war? No. Hopefully it can save us from the most serious sort of war, namely great-power war—but even that’s not guaranteed. Unfortunately, nuclear deterrence isn’t a set-and-forget sort of thing.

But nor should we assume that nuclear war is inevitable, or that any crossing of the threshold automatically heralds the end of civilisation. If deterrence does break, we want it to do so in small packets, minimising the prospects for early targeting of cities, and maximising our prospects for de-escalation and war termination.

Andrew argues that if we want to enjoy a lively chat with our interstellar neighbours in the future, then keeping nuclear weapons around is just dumb. I think I’d reverse that judgement: I see no sense in pulling down the long pole in the tent of international security in the hope of meeting ET. ET might never visit—or even be friendly.

On the eve of destruction? (Part 2)

As I described in my previous piece, I’ve recently come around to the view that we need to do something to reduce the probability of a civilisation-ending nuclear exchange. Put like that, it sounds like a no-brainer, but I received quite a bit of pushback from strategists I sent a draft to. I’ll respond to the arguments they raised here.

As foreshadowed in part 1, there was the predictable argument that the world has become safer since the advent of nuclear weapons, because they have appreciably reduced the incidence of major conflict. I would have said that once as well, but looking at the problem through a statistical lens, I don’t believe it’s true. While we haven’t seen violence on the scale of the two world wars, that’s a very poor measure of relative peace. As Lewis Richardson points out in his statistical analysis of wars, those are the only two ‘magnitude 7’ wars (i.e. more than 10 million deaths) in human history. Saying we’re safer now than we were in World War II is a bit like saying the earth is cooling because last year was slightly less hot than the previous year. The temperature reduction between 2016 and 2017 is true, but in isolation it doesn’t accurately reflect the underlying dynamics.

There’ll be excursions around the mean in any noisy dataset. Interpreting those as systemic trends is incorrect. Since World War II, there have been as many magnitude-6 wars (over a million deaths) as in previous half-centuries, including both interstate wars (Korea and Vietnam) and civil wars (China and Rwanda). There’s a magnitude-5 war underway at the moment in Syria, and the conflict in Yemen could easily reach that level. And many of the Cold War conflicts involved proxies of the two competing blocs—as mirrored in the Syrian conflict today. Time will tell if nuclear weapons have really calmed things down, but I’d be surprised if the apparent current period of relative peace is statistically significant—though the increased global population might have reduced the per capita risk of death in conflict.

Another popular argument was that the near misses of the Cold War provide confidence that we can safely negotiate crises. That’s deeply worrying. Ellsberg points out that if one or two individuals had acted differently at key moments, we wouldn’t be here having this argument today. Two especially close calls were on board the Soviet submarine B-59 during the Cuban missile crisis, when the decision to not fire a nuclear-tipped torpedo came down to one man overriding another, and the ‘Able Archer’ NATO exercise of 1983, which almost set off a Soviet nuclear strike. (You can read Paul Dibb’s account of the 1983 event here.)

To take comfort from those events (and others, including the moon being mistaken for an incoming Soviet missile with over 99% confidence), you have to argue that there’ll always be one or more of the right people in the right place at the right time to intervene to head off disaster. Instead, those incidents are evidence of the very substantial risks that exist, and of the very thin margins by which we have managed to not realise those risks so far. When playing Russian roulette, two successive ‘clicks’ shouldn’t provide greater confidence that future trigger pulls will also end happily. To get quantitative, if the odds of a crisis event being mismanaged is as low as 10% (and that seems pretty generous in some of the documented instances), then on average we get to roll the dice just six times before disaster strikes.

A related argument was that delegation of nuclear responsibility is actually a good thing when the leadership of nuclear-armed states is unreliable, such as mercurial leaders like Donald Trump and Kim Jong-un. In that case, one respondent argued, it’s good to have the possibility of someone else saying ‘no’. But that relies on level heads being in all of the right places further down the chain of command on both sides. And having inexpert leaders who are prone to creating crises surely outweighs the dubious benefits of a longer command chain.

I did get one argument that’s more convincing—that ‘you can’t get there from here’. The current reality is that nuclear weapons exist, and states in possession of them aren’t likely to agree to do away with them, especially when that creates a strong incentive for others to cheat on the deal. That’s likely true, but it doesn’t mean that we have to settle for a perpetual existential threat. Ellsberg convincingly explains that a single nuclear detonation in Washington or Moscow, regardless of its origin, could be the beginning of the end.

There are policy approaches that could substantially reduce the risk of global catastrophe. For a start, we should continue to take every possible step to prevent further proliferation of nuclear weapons. More fingers on more triggers would be worse. And that goes for us—Australia’s position should be ‘no nukes’, regardless of any possible future degradation of the US security guarantee. Another approach might be an international treaty that prohibits fusion weapons and limits yields to kilotons rather than megatons. Given the accuracy of modern delivery systems, large-yield weapons shouldn’t be required for nuclear deterrence to hold. (Reducing the total world holding to levels below that required to produce a nuclear winter is not a new idea, and dates back to the 1980s.)

That said, I’m not holding my breath. Humans don’t seem to be particularly good at dealing rationally with existential threats. I’ll give the last word to one of my strategic studies students from ANU. I was discussing the management of risk, and offered a large cometary impact as an example of a low likelihood but extreme outcome event (ask T. rex how that worked out). I speculated about the global response if astronomers spotted a comet with a 5% probability of hitting earth in the next century. The student’s comment was that, ‘If global warming is anything to go by, comet denial would become a thing.’ It’s darkly funny, but I think we’ve also been in nuclear denial for a long time.

 

Further reading

Daniel Ellsberg, 2017, The doomsday machine: confessions of a nuclear war planner.

Brian Hayes, 2002, ‘Computing science: statistics of deadly quarrels’, American Scientist, vol. 90, no. 1 (summary of findings in Lewis F. Richardson, 1960, The statistics of deadly quarrels (out of print)).

Richard Rhodes, 2008, Arsenals of folly: the making of the nuclear arms race.

If the US nuclear umbrella folds … The choices for Australia

Rod Lyon’s thought-provoking article in The Strategist concludes with a sobering choice for Australian defence planners considering a post–San Francisco world without US extended nuclear deterrence, and suggests two basic choices for Australia, Japan and South Korea:

They can either head down the path of developing indigenous nuclear arsenals, or they can attempt to dilute the advantages that nuclear weapons confer—advantages which would otherwise accrue to a set of states that did not wish them well.

Both Japan and South Korea have the technological means to rapidly develop independent nuclear deterrent capabilities, though neither state would have strong popular support for such a move. For Australia, it’s a bit more complicated. The issue of Australia ‘going nuclear’ has already been considered in numerous articles, and 2018 began with a bang in The Strategist with a discussion on Australia’s nuclear options by key authors such as Hugh White, Andrew Davies and Stephan Frueling, and in an ASPI Strategic Insights report by Paul Dibb and Richard Brabin-Smith. I contributed my thoughts, too.

The complexity and cost of getting the warheads and acquiring a credible delivery system would probably push Australian defence spending well past the 2% GDP target that we currently aspire to. Maybe President Donald Trump’s proposed 4% GDP target for NATO would be more appropriate as a starting point for an Australia considering nuclear weapons.

There would be political consequences for Australia of moving away from its traditional policy of fully supporting the Nuclear Non-Proliferation Treaty, and Australia would violate the South Pacific Nuclear-Free Zone Treaty in getting nuclear weapons. Any Australian move towards nuclear weapons could prompt counter-responses from our immediate neighbours and accelerate the erosion of non-proliferation norms.

If we had to go nuclear, we’d not only need the infrastructure to develop and then sustain the nuclear forces we acquired (which means significant upfront and ongoing investment); we’d also have to think seriously about Australian nuclear strategy and doctrine to ensure we did deter effectively. Nuclear weapons and deterrence is a deadly serious business—it’s not about bluffing. An Australian nuclear option would have to embrace a warfighting capacity that we’d need to be willing to use.

The most obvious choice for force structure would be continuous at-sea deterrence on submarines. But the Shortfin Barracuda SSK isn’t designed for nuclear deterrence, and adding such a capability could limit its operational and tactical flexibility. And it takes time to develop such a capability, so if events continue to move quickly, we might simply be too late to respond and too slow to act.

If nuclear weapons are challenging, what about alternatives? Rod talks about trying to ‘dilute the advantages that nuclear weapons confer’. How Australia might achieve that objective goes to the question of whether non-nuclear capabilities can effectively deter nuclear threats.

A ballistic missile defence (BMD) system is commonly seen to be a non-nuclear counter to nuclear threats, but in reality the advantage always goes to the offence. It’s cheaper to build more missiles or equip existing missiles with MIRV capabilities and overwhelm missile defences. US national missile defence is hideously expensive and not that effective. Even the US Navy’s ship-based SM-3 interceptors are tested only under highly controlled conditions.

Certainly, there are options that under the right circumstances could allow pre-emptive strikes ‘left of launch’ to prevent use of nuclear weapons. That would demand intelligence which is persistent and penetrating of an adversary’s leadership and command and control, and that is exceedingly difficult with likely major power threats. It would also demand a prompt-strike capability, based on either effective offensive cyberwarfare or forward-deployed precision kinetic strikes against missiles. There’s no guarantee that such a capability could be developed, even by the United States, let alone Australia.

Rather than trying to counter nuclear threats symmetrically, an indirect and asymmetric approach might be better. Australia could consider acquiring the means to prevent a major-power adversary from projecting power against our vital strategic interests, including our air and maritime approaches, by developing anti-access and area denial (A2AD) capabilities that focus on the South China Sea and exploit vital maritime straits and chokepoints throughout Southeast Asia.

Australian A2AD would ideally focus on a tactical and operational offensive attack at source rather than maintain a traditional defence-in-depth strategy. It would imply the ADF acquiring substantial air and sea capabilities suitable for rapid long-range strikes with precision non-nuclear weapons in sufficient mass to generate a meaningful effect, alongside developing more robust cyber and electronic warfare attack capabilities.

The objective would be to rob an opponent of the military capability needed not only to project power aggressively against us, but also to weaken it in comparison with other regional actors, such that it then would be poorly placed to defend its other strategic interests. Striking at vital interests of the opponent could also imply attacking national economic resilience in a way that threatens the political survival of a regime. Together, these factors could raise the cost of aggression to unacceptable levels, and thus, hopefully, deter such aggression, without resort to nuclear weapons.

The problem with this indirect strategy is that it would require a substantial expansion of the ADF at great cost, and take considerable time. The nominal 2% of GDP target of the 2016 defence white paper would easily be breached. There’s also a risk that an adversary with far larger forces could do the same to us, and, as a smaller actor, we’re likely to be less resilient. Finally, in the absence of an Australian nuclear-weapons capability, the nuclear-armed major-power adversary always has escalation dominance.

Rod’s initial question therefore stands and poses a strategic dilemma for Australia in an unpredictable outlook. We could develop a combination of alternatives—BMD (accepting its limitations), ‘left of launch’ pre-emption, and A2AD—in the absence of US extended nuclear deterrence, at great cost. Yet that still leaves us potentially facing a serious nuclear threat with no guarantee that these non-nuclear options will work as an effective deterrent in a major crisis.