The third nuclear age and nuclear stability


The ‘Third Nuclear Age’ is upon us, writes Sylvia Mishra, and it is an age fraught with new dangers, from the digitalization of warfare and unknown outcomes to the collapse of arms control structures that maintained strategic stability. But what is strategic stability?

“The concept of ‘stability’ is a fuzzy one, partly because there is no clear-cut agreement among those who use the term so precisely what the trends and events are that might upset the balance and what the relative likelihoods are”.

Thomas C. Schelling & Morton H. Halperin. [1]

In the Cold War strategic stability was defined by the United States, and the former Soviet Union as the absence of incentives for any country to launch a first nuclear strike.

Although the concept and conditions for what is strategic stability have since changed, there is still no consensus among rival nuclear powers on what the term ‘strategic stability’ means and what principles of ‘strategic stability’ entails.[2]

In the 21st century against the backdrop of multipolar nuclear rivalries and multiple nuclear deterrent relationships, it is imperative that nuclear-armed countries engage in constructive dialogue to develop greater clarity of the other’s understanding of strategic stability so as to better manage nuclear crises.

At a time when nuclear weapons are rapidly gaining salience in military warfighting doctrines, communication and dialogue among states is key to a shared understanding of mutual vulnerabilities. Beyond the ambit of the Nonproliferation Treaty (NPT), the United States should take the lead to establish a framework maintaining strategic stability in a multipolar nuclear order and engage nuclear-armed countries outside the NPT.

Arms Control and Strategic Stability

In the February 2018 Donald Trump administration Nuclear Posture Review (NPR) Report, prominence[3] is given to the concept of strategic stability. It has been thoroughly discussed in other policy documents as well: the National Security Strategy (NSS) of December 2017 stresses that the US will consider new arms control arrangements if they contribute to strategic stability.[4]

The NPR addresses the present and future of US nuclear weapons policies[5] in an evolving and uncertain international security environment. It underscores the value of US. nuclear capabilities, and addresses the challenges posed by Russian, Chinese, and other states’ strategic policies. It maintains that flexible, adaptable and resilient U.S. nuclear capabilities are required to protect the US, its allies and partners and promote strategic stability.

For effective US deterrence against nuclear attack and non-nuclear strategic attack the NPR calls for a diverse range and mix of US deterrence options to ensure strategic stability. The policy document says the US is committed to arms control efforts which can contribute to its capability to sustain strategic stability.

The concept of strategic stability presents itself often in different government documents and other policy reports. What is strategic stability? Why do successive US. governments accord high priority to sustaining and maintaining strategic stability with Russia and China?

Is strategic stability good for global peace and security? What are the origins of the concept? What are the key concepts and guiding tenets for the theory of strategic stability? Has the meaning of strategic stability evolved over time?

 The central ideas that underpin the concept of strategic stability date back to the early 1950s and the concept grew out of a “logical progression in thinking about the consequences of the nuclear revolution, the challenge of a surprise attack…and the requirements of credible deterrence”.[6] While the concept regularly features in discussions and debates on nuclear policy issues, it is used as a concept without a common definition – there is no single, universally accepted definition of stability or agreed-upon metrics to measure it.[7]

The late US foreign policy adviser John D. Steinbruner defined strategic stability as a characteristic of deterrence based on mutual assured destruction (MAD),measured largely in terms of the potential vulnerability of strategic force components.[8] In the Cold War, the logic of strategic stability dictated that responsible, rational leaders would refrain from hostilities threatening the survival of their nation.

Deterrence in the context of bipolar nuclear rivalry was, therefore, relatively straightforward and the dominant relationship was simple – one enemy, one threat, one strategy.[9] But as bipolarity gave way to the emergence of new threats, a security strategy and policy cannot be solely premised on the belief that numbers and firepower will deter aggression.

While the broader tenets of strategic stability still exist, the new deterrence relationships require tailored strategies.

Read the second part of this commentary later this week.

[1] Thomas C. Schelling & Morton H. Halperin, ‘Strategy and Arms Control’, 1985

[2] Eds. Lawrence Rubin and Adam M. Stulberg, “The End of Strategic Stability? Nuclear Weapons and the Challenge of Regional Rivalries”, (George Washington University Press, Washington DC, 2018)

[3] ‘Nuclear Posture Review’, Department of Defense, February 2018, available at

[4] ‘National Security Strategy of the United States of America’, The White House, December 2017, available at

[5] ‘Nuclear Posture Review’, Department of Defense, February 2018, available at

[6] Elbridge A. Colby & Michael S. Gerson, ‘Strategic Stability: Contending Interpretations’, Strategic Studies Institute and U.S. Army War College Press, February 2013, available at

[7] Ibid.

[8] John D. Steinbruner, ‘National Security and the Concept of Strategic Stability’, available at

[9] Frank P. Harvey, ‘The Future of Strategic Stability and Nuclear Deterrence’,  International Journal, Vol. 58, No. 2 (Spring, 2003), pp. 321-346, available at