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South African Journal of Military Studies
Hypersonic weapons and the future of nuclear
deterrence
Eben Coetzee
130
Department of Political Studies and Governance,
University of the Free State
Abstract
It is widely accepted today that hypersonic weapons pose insurmountable challenges
to nuclear deterrence. Although speed has always been a critical factor in warfare, the
development of hypersonics provides unprecedented advantages in terms of the speed
and agility of missiles. The increase in the speed and agility of hypersonic missiles
drastically reduces the response time of nuclear states, encouraging the pre-emptive use
of force. Two arguments inform the latter claim. The rst holds that the speed and agility
of hypersonic missiles are likely to render existing and future missile defences obsolete.
The second contends that the failure of missile defences coupled with the reduction
of the response time of nuclear states encourages the pre-emptive use of force. Where
nuclear states are unable to eld survivable second-strike forces, the stability of nuclear
deterrence becomes highly problematic. Besides these arguments, the dual-use nature of
hypersonic weapons ostensibly increases the risk of nuclear escalation. Against this bleak
assessment, in this article, the author questions the destabilising eects of hypersonic
weapons on deterrence stability, arguing that nuclear deterrence is – and is likely to
remain – deeply stable. A thoroughgoing consideration of the strategic implications
of nuclear weapons provides optimism about the stability of nuclear deterrence in
the face of the development of hypersonic weapons. Two arguments are advanced in
support of the continuing stability of nuclear deterrence. First, missile defences have
(and are likely to remain) inecacious, with the development of hypersonic weapons
merely reinforcing (rather than establishing) this fact. Second, a would-be aggressor
contemplating the pre-emptive use of force would have to believe that it could destroy
all of an adversary’s nuclear force before any can be launched.
Keywords
Hypersonic weapons; nuclear deterrence; war; emerging technologies; missile
defence
Introduction
Concerns over the potentially destabilising eects of hypersonic weapons on
deterrence stability are mounting. The term ‘hypersonic’ denotes aircraft, missiles,
rockets, and spacecraft capable of travelling through the atmosphere at speeds exceeding
5 000 kilometres per hour or Mach 5.
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The development of hypersonics is believed to
be a game-changer technology. James Miller, the principal advisor to the United States
(US) High-Speed Systems Division of the Air Force Research Laboratory (AFRL) at the
Scientia Militaria: South African Journal of Military Studies, Vol 49, Nr 1, 2021. doi: 10.5787/49-1-1318
