Abstract
Today, it is widely argued and, within certain military and academic circles, unequivocally accepted that various military-technological developments render the second-strike forces of nuclear states increasingly vulnerable. Where the second-strike forces of nuclear states become increasingly vulnerable, a strategy based on deterrence becomes inefficacious, thus increasing the prospect of a pre-emptive attack. The second-strike forces of nuclear states have traditionally been rendered invulnerable by deploying the so-called “nuclear triad” consisting of intercontinental ballistic missiles (ICBMs), strategic bombers, and ballistic missile submarines (SSBNs). Given the patent shortcomings of ICBMs and the (apparent) vulnerability of strategic bombers to missile defences, the quiet submarine has traditionally been considered the least vulnerable leg of the nuclear triad. Moreover, SSBNs are deemed highly efficacious platforms due to their stealth and attendant ability to penetrate enemy defences and conduct various missions.
However, sweeping technological developments in remote sensing, coupled with the shift towards unmanned sensors and sensor platforms, will ostensibly make the oceans increasingly transparent, thus rendering SSBNs increasingly vulnerable to detection and, possibly, destruction. Five trends undergird arguments that developments in remote sensing are making the oceans more transparent: one, sensor platforms have become increasingly diverse; two, the spectrum of signals collected by sensors, and the techniques used for this purpose, have widened; three, remote sensing platforms are increasingly marked by persistent observation; four, part of the revolution in remote sensing is the attendant ongoing improvement in sensor resolution; and finally, these four developments are undergirded by improvements in data transmission. In the battle between hiders and seekers or, differently phrased, submarines and anti-submarine warfare (ASW), the pendulum is, it seems, swinging in the direction of the latter. Accordingly, nuclear states are likely to find it increasingly difficult in the future to conceal SSBNs from the “eyes” and “ears” of ASW forces.
The primary research question of this study is: Against the backdrop of sweeping technological developments in ASW, how vulnerable are SSBNs as the cornerstone of the second-strike forces of nuclear states really and what are the implications for nuclear deterrence that follow from this? The study is based on a literature study of the evolution of ASW (from the early development of the submarine to the current era) while also paying particular attention to various developments in submarine development and warfare. The conclusion reached from this analysis is that pessimism concerning the (future) vulnerability of SSBNs is unfounded and that the stability of nuclear deterrence is likely to endure remarkably well in the future. Based on examining historical and current developments in ASW and submarine warfare, four key findings are derived that inform the conclusion reached.
Firstly, to detect, trail and, most importantly, destroy a single SSBN (let alone an entire SSBN force) is hardly an easy task. Thus, even if some technologies may facilitate the detection of submarines in the future, the problem of destroying a single SSBN (again, let alone an entire SSBN force) remains a particularly vexing one. Secondly, the history of ASW provides powerful evidence that developments in military technology are never unidirectional. Thus, where innovative ASW developments and solutions emerge, it stands to reason that we can also expect innovative pro-submarine developments, strategies, tactics and solutions. In fact, such pro-submarine developments are already unfolding and keeping pace with ASW developments.
Thirdly, technological developments in ASW have never yielded a definitive victory in the battle against the detection, trailing and, most importantly, the destruction of SSBNs, a proposition that is likely to endure remarkably well in the future. Even the best surveillance and detection systems are fraught with limitations. Moreover, a successful ASW strategy requires the successful integration of multiple independent factors, inter alia, multiple ASW forces, highly efficacious ASW concepts, considerable investment, maritime geography, and the expertise of ASW forces. There is today only one navy (i.e. the United States Navy) capable of engaging in full-spectrum ASW, a feat that should not conceal the harsh reality that even the US Navy cannot detect, trail and, importantly, destroy all the SSBNs – and all of them at once – of an adversary.
Finally, the history of ASW powerfully attests to the importance of maritime geography and, concomitantly, oceanography for both ASW and submarine concealment. Current and future acoustic surveillance systems are likely to remain dependent on real estate for signal processing. The concomitant result is that maritime geography will be more favourable to some states than others. At the same time, oceanographic data are becoming increasingly voluminous owing to the use of underwater gliders, which in turn strengthens submarine efforts to operate more quietly and avoid detection. In addition, the growing industrial use of the oceans, coupled with the increase in the number of states deploying (and yet to deploy) submarines, will further hamper efforts to detect SSBNs.
Accordingly, this analysis illustrated that sweeping developments in particularly remote sensing would not render the pre-eminent pillar of states’ second-strike forces, to wit SSBNs, increasingly vulnerable. Nuclear deterrence is likely to endure remarkably well in the future. Emerging technological developments, notably big data, artificial intelligence, and quantum computing, are often envisioned as key developments that will most likely increase the efficacy of ASW forces by 2050. Unlike developments in remote sensing, such possible future developments, and their implications for ASW and submarine warfare, are too vague to assess today. At any rate, three reasons provide grounds for optimism concerning the future invulnerability of SSBNs and the stability of nuclear deterrence, notwithstanding the future direction of technological development. One, it is highly unlikely that any future technology will render the oceans completely transparent. Two, the history of ASW powerfully illustrates that the battle between submarines and ASW forces is an ongoing one. In this battle, it is improbable that developments in ASW will ever yield a definitive victory for ASW forces. Finally, and undoubtedly the most important reason, even if some or other technology facilitates the easy detection of SSBNs, a strategy of nuclear deterrence will only be upended, and the possibility of a pre-emptive attack increased, if a would-be aggressor believes that all the SSBNs of a nuclear state can be destroyed and all of them at once. Accordingly, today and in the foreseeable future, we have sufficient grounds for believing that SSBNs are likely to remain the least vulnerable leg of the nuclear triad.
Keywords: anti-submarine warfare (ASW); ballistic missile submarines (SSBNs); nuclear deterrence; nuclear weapons; sensors; submarines