The Problem of Blurring Conventional and Nuclear Deterrence
The world is witnessing a trend of countries increasingly integrating conventional and nuclear deterrence concepts, war-fighting plans, and threatening rhetoric. Such moves resurrect dangerous Cold War-era concepts, and depart from some of the stabilizing measures that countries have adopted since that time. This essay describes the most prominent ways in which this ‘blurring’ is taking place, and the dangers inherent in this trend.
Integration of conventional and nuclear deterrence
The blurring of conventional and nuclear deterrence is occurring in at least two distinct ways. The first involves the increasing integration of conventional and nuclear war-fighting in ideas of how specific conflicts may be carried out, and therefore what constitutes effective deterrence in such scenarios. Most countries long held the view that nuclear weapons are exceptional and represent a dramatic type of escalation if used, and that such use would drive a distinctly different and unpredictable set of responses compared with the use of non-nuclear assets. The inability to predict or control escalation in nuclear war was held as an important aspect of these weapons’ deterrent effects.
Most countries long held the view that nuclear weapons are exceptional and represent a dramatic type of escalation if used, and that such use would drive a distinctly different and unpredictable set of responses compared with the use of non-nuclear assets.
Some officials and scholars are now embracing the notion that the use of nuclear weapons – at least those of a relatively lower yield – against specific types of targets does not represent an entirely distinct realm of military action. Rather, such use would represent merely a step up the ‘escalation ladder’ whereby the impact of the use of a low-yield nuclear weapon would not be terribly different from a large-scale conventional attack. For example, in 2016 Robert Scher, then US Assistant Secretary of Defense for Strategy, Plans, and Capabilities, testified of ongoing efforts to merge conventional and nuclear war-fighting plans, stating that such ‘integration means being prepared to restore deterrence following adversary nuclear use, so that failure to deter first use does not translate into failure to deter subsequent nuclear use’.
This concept is not altogether new; on the contrary, it mirrors some deterrence concepts that informed Soviet and US deployment of tactical nuclear weapons during the Cold War. In addition, over the past decade, Pakistan and India have had their own takes on integrating conventional and nuclear planning.
The US and Russia are now reinvigorating the Cold War concepts. Concern spread over the past decade that Russia held an ‘escalate to de-escalate’ strategy, by which it may use a relatively low-yield nuclear weapon in an otherwise conventional conflict in order to halt a trajectory of further conventional escalation. Some Russian leaders have denied that they maintain such a policy. In the meantime, the concept made its way into US thinking on deterrence, being most explicitly formulated in the 2018 Nuclear Posture Review (NPR). Such tight weaving of nuclear use into otherwise conventional planning has become increasingly standard in the US in recent years, and is now more commonly debated for scenarios involving North Korea, in addition to Russia.
A second type of blurring lies in nuclear responses to – and therefore deterrence of – non-nuclear attacks. For the US, the 2018 NPR increased focus on the possibility of nuclear weapons use in response to significant non-nuclear attacks. It noted that the US will:
… posture our nuclear capabilities to hedge against multiple potential risks and threat developments. We will, for example, hedge against the potential rapid growth or emergence of nuclear and non-nuclear strategic threats, including chemical, biological, cyber, and large-scale conventional aggression.
Notably, this shift followed international concern that India’s deterrence doctrine maintained the possibility of nuclear retaliation in the event of major chemical or biological weapons attacks. The case of India highlights the limits and dangers of this nuclear–conventional co-mingling: chemical or biological attacks can be carried out by non-state actors; those actors may or may not be perceived as being sponsored by another state; and attribution of such attacks could be highly uncertain. Similar – and in some cases far more severe – attribution challenges could stem from large-scale cyberattacks.
These changes stem from numerous technological and political evolutions. Over several decades, the US’s increasing missile defence and conventional superiority was among the factors causing Russia to question whether its nuclear deterrent remained effective, and through this process, come to reassess its nuclear posture. On the US side, some changes grew from concern over Russia’s nuclear modernization, and other actions including its annexation of Crimea and interference in US elections.
Concepts that blur conventional and nuclear deterrence also emerged, in part, from nuclear arsenal reductions by the US and the Soviet Union/Russia. While nuclear weapons numbers remain substantial, some (though not all) experts from the US and Russia are uncomfortable with the idea that deterrence can be maintained at lower than Cold War levels. This has led to work being done to develop new deterrence concepts, including a renewed focus on lower-yield nuclear weapons, on the premise that nuclear capabilities must be diverse and politically ‘usable’ in order to effectively deter adversaries. Such concepts point to the need for new nuclear capabilities, which are further fostered by those who could benefit from these new lines of large-scale defence procurement.
Problems arising from integration
Both ways of blurring conventional and nuclear deterrence have major faults, and in some scenarios may increase the likelihood that nuclear weapons will be used. It could be assumed that policies to intertwine nuclear and non-nuclear deterrence are meant to focus only on worst-case scenarios: one such scenario might be a conflict in which the use of a massive chemical attack is seen as a prelude to nuclear weapons use, and perhaps shows indiscriminate use against civilian targets. Even so, many issues arise.
First, credibility is a core requirement for effective deterrence. Many observers question whether it is credible to believe that countries such as India or the US would truly use nuclear weapons in response to a non-nuclear attack. These policies may therefore stoke fears without effectively deterring aggression.
Second, it is a flawed premise that escalation can ever be predictable and controllable if a country moves from conventional to nuclear conflict. This idea was long rejected by civilian and military leaders globally, and most still believe it to be a dangerous line of thinking for several reasons.
There is no certainty that a country’s adversaries or its own future decision-makers will interpret policies and plans in an identical fashion. While a country’s officials may integrate conventional and nuclear planning for use only after strategic non-nuclear attacks, a future leader of that nation may hold a much lower bar for what is considered strategic attack; such a bar, for example, is not defined in the cyber realm.
While a country’s officials may integrate conventional and nuclear planning for use only after strategic non-nuclear attacks, a future leader of that nation may hold a much lower bar for what is considered strategic attack.
Various countries hold differing deterrence theories and cultures, and differing definitions of strategic stability. They are liable to interpret signals differently from how the signaller may have intended. Particularly in conflict, or in a quickly escalating crisis, it would be dangerous to believe that all sides would respond predictably.
Differences in definitions of core concepts across countries also influence whether the merging of conventional and nuclear deterrence could heighten risks. The US, for instance, differentiates between strategic versus non-strategic non-nuclear attacks (whether chemical, biological or cyber). Yet there is no global definition of that line. For smaller countries, or those with a history of foreign takeover, any nuclear threat can be existential. Likewise, the scale of non-nuclear attacks that could imperil smaller states’ populations or sovereignty beyond risk tolerance is itself smaller than for those with vast military power and dispersed populations and assets. And even within countries, there is no monolithic definition: doctrines and definitions related to potential nuclear use change over time, and perspectives regarding thresholds and specific weapon effects vary among experts.
Moreover, deterrence concepts inform nuclear weapons procurement decisions that may then heighten anxiety and risk of misinterpretation with other countries. In 2000, notably, the US Central Intelligence Agency (CIA) concluded that: ‘Moscow’s military doctrine on the use of nuclear weapons has been evolving and probably has served as the justification for the development of very low-yield, high-precision nuclear weapons.’
For years, the US refrained from mirroring this development of new nuclear capabilities, as its existing deterrent and proportional response options were strong. More recently, the US pivot towards a greater integration of conventional and nuclear deterrence informed its investment in a new wave of low-yield nuclear options. These types of weapon are designed to be more usable by political leaders than even more destructive nuclear options. Indeed, the 2000 CIA memo commented that Russia’s focus on new low-yield nuclear weapon capabilities and related doctrine ‘lower the threshold for first use of nuclear weapons and blur the boundary between nuclear and conventional warfare’.
Additionally, some same systems are of dual conventional and nuclear capability, which can increase the risk of catastrophic miscalculation. For instance, according to President Putin in 2018: ‘Only when we become convinced that there is an incoming attack on the territory of Russia, and that happens within seconds, only after that we would launch a retaliatory strike.’ In the case of US dual-capable cruise or ballistic missile systems, a conventional attack mistaken for a nuclear one could trigger an unintended escalation to nuclear conflict.
These types of heightened risks – stemming from the greater integration of conventional and nuclear deterrence concepts and extending into the development of specific nuclear capabilities – show that there would be significant security value in re-establishing starker lines that hold nuclear weapons as exceptional. As NATO Secretary General Jens Stoltenberg stated in 2016:
For NATO, the circumstances in which any use of nuclear weapons might have to be contemplated are extremely remote. But no one should think that nuclear weapons can be used as part of a conventional conflict. It would change the nature of any conflict fundamentally.
117 Scher, R. (2016), Statement before the Senate Armed Services Subcommittee on Strategic Forces, 9 February 2016, https://www.armed-services.senate.gov/imo/media/doc/Scher_02-09-16.pdf (accessed 14 Aug. 2019).
118 Ryan, K. (2020), ‘Is ‘Escalate to Deescalate’ Part of Russia’s Nuclear Toolbox?’ Russia Matters, 8 January 2020, https://www.russiamatters.org/analysis/escalate-deescalate-part-russias-nuclear-toolbox (accessed 14 Feb. 2020).
119 Office of the Secretary of Defense (2018), Nuclear Posture Review, pp. 30–1.
120 Ibid, pp. 37–8.
121 Chari (2014), ‘India’s Nuclear Doctrine: Stirrings of Change’.
122 See Gower, J. (2019), Improving Nuclear Strategic Stability Through a Responsibility-Based Approach: A Platform for 21st Century Arms Control, Council on Strategic Risks Briefer, No. 1, 7 January 2019, https://councilonstrategicrisk.files.wordpress.com/2019/01/improving-nuclear- strategic-stability-through-a-responsibility-based-approach_briefer-1_2019_01_7.pdf (accessed 14 Aug. 2019); Zhao, T. (2019), ‘What the United States can do to stabilize its nuclear relationship with China’, Bulletin of the Atomic Scientists, 2 January 2019, https://thebulletin.org/2019/01/what-the-united-states-can-do-to-stabilize-its-nuclear-relationship-with-china/ (accessed 14 Aug. 2019).
123 Office of the Secretary of Defense (2018), Nuclear Posture Review.
124 US Central Intelligence Agency (2000), Evidence of Russian Development of New Subkiloton Nuclear Warheads, Intelligence Memorandum, p. 6, https://www.cia.gov/library/readingroom/docs/DOC_0001260463.pdf (accessed 14 Aug. 2019).
125 Ibid, p. 1.
126 Isachenkov, V. (2018), ‘Russia is ‘ahead of competition’ with latest weapons, but won’t use nukes first, Putin says’, Military Times, 18 October 2018, https://www.militarytimes.com/news/your-military/2018/10/18/russia-is-ahead-of-competition-with-latest-weapons-but-wont-use-nukes-first-putin-says/ (accessed 14 Aug. 2019).
127 Weber, A. and Parthemore, C. (2019), ‘Smarter US modernization, without new nuclear weapons’, Bulletin of the Atomic Scientists, 2 January 2019, https://thebulletin.org/2019/01/smarter-us-modernization-without-new-nuclear-weapons/ (accessed 14 Aug. 2019).
128 Stoltenberg, J. (2016), ‘Speech by NATO Secretary General Jens Stoltenberg at the Munich Security Conference’, NATO, 13 February 2016, https://www.nato.int/cps/en/natohq/opinions_128047.htm (accessed 14 Aug. 2019).