The Congressional Commission on the Strategic Posture of the United States issued its final report in October 2023. Because of the ongoing wars in the Middle East and Ukraine, it did not receive the attention it should have given the critical role of nuclear weapons in our security. The report contends that, although the fundamentals of the U.S. deterrence strategy remain sound, the application of that strategy must change significantly to address the 2027-2035 threat environment. According to the report, the U.S.-led international order and the values it upholds “are at risk from the Chinese and Russian authoritarian regimes,” and the risk of military conflict with those major powers has grown and “carries the potential for nuclear war.” As the Commission argues:

Today the United States is on the cusp of having not one, but two nuclear peer adversaries, each with ambitions to change the international status quo, by force if necessary, a situation which the United States did not anticipate and for which it is not prepared. While the risk of a major nuclear conflict remains low, the risk of a military conflict with either or both Russia and China, while not inevitable, has grown, and with it the risk of nuclear use, possibly against the U.S. homeland.

To meet this and other foreseeable national security challenges, the Commission recommends an ambitious program of nuclear and conventional force modernization, a more resilient space architecture with offensive and defensive elements, an expansion of the U.S. defense industrial base, improved nuclear infrastructure, and, where appropriate, nuclear arms control and-or measures of nuclear risk reduction. In addition, it argues that the United States should ensure that it is on the cutting edge of emerging technologies related to security and defense, including big data analytics, quantum computing, and artificial intelligence (AI). 

Included in the Commission’s recommendations is the completion of existing plans for the modernization of the U.S. strategic nuclear triad of intercontinental land-based, sea-based, and airborne nuclear delivery systems and warheads. This program more or less tracks the consensus of the Obama, Trump, and Biden administrations, although the Commission recommends possible increases in the hitherto projected numbers of sea-based and airborne nuclear launch systems. According to the Commission, U.S nuclear strategy should be based on six fundamental tenets: (1) assured second strike; (2) flexible response to achieve national objectives; (3) tailored deterrence; (4) extended deterrence and assurance; (5) calculated ambiguity in declaratory policy; and (6) hedge against risk. 

It contends that flexible response should provide a credible range of resilient response options to restore nuclear deterrence and promote conflict termination by “convincing an adversary’s leadership it has seriously miscalculated, that further use of nuclear weapons will not achieve its objectives, and that it will incur costs that far exceed any benefits it can achieve should it escalate further.”

Although the Commission includes both conventional and limited nuclear options in its recommended tool kit for deterrence and assurance, it is clear that it views current U.S. non-strategic weapons as insufficient for probable future deterrence stress tests. In this view, it is not alone. The Nuclear Posture Reviews (NPRs) of the Obama, Trump, and Biden administrations largely agreed about the size and composition of U.S. strategic nuclear forces. On the other hand, their perspectives on lower-yield or non-strategic nuclear weapons differed. The Obama administration deemphasized non-strategic nuclear weapons, but the Trump administration proposed two new weapons to offset perceived deficiencies in U.S. flexible nuclear response: a low-yield version of the W76 warhead for the Navy’s Trident D-5 submarine-launched ballistic missile (SLBM); and a new nuclear-capable submarine-launched cruise missile (SLCM-N). The Biden administration chose to retain the low-yield D-5, but its 2022 NPR excluded any plans to develop the SLCM-N. In accessing the Commission’s recommendations, it is important to keep in mind the perspectives of several experts and other factors. 

Keith B. Payne and David J. Trachtenberg, both former high-ranking defense department officials, have noted that Russia and China continue to build additional non-strategic nuclear weapons (NSNW) and that Russia’s stockpile of deployed NSNW maybe ten times or more the number of a similar American weapon. The result of disparities in NSNW between the U.S. and Russia or China could be gaps in the spectrum of deterrence and assurance. According to Payne and Trachtenberg,

In the near-absence of proportional, regional U.S. nuclear capabilities, deterrence could fail because Russia and China understandably question whether the United States would be willing to turn a regional conflict into a potentially suicidal nuclear war, and thus calculate that they are in greater freedom to engage in regional, limited nuclear threats or employment.

Mark B. Schneider, a senior career Pentagon and State Department official, also points to potential deterrence vulnerabilities in the larger Russian numbers of non-strategic nuclear weapons compared to those available to U.S. forces:

There are very large numbers of potential targets for low yield/low collateral damage battlefield nuclear weapons. If the United States seeks to keep a conflict limited by refraining from strategic weapons use, it will clearly be at a significant disadvantage in non-strategic nuclear force numbers. Indeed, the more the United States seeks to keep the nuclear conflict limited by creating a firebreak between non-strategic and strategic nuclear weapons, the more significant the Russian nuclear advantage will become.

As far back as 2019, Lt. Gen. Robert P. Ashley, then head of the U.S. Defense Intelligence Agency (DIA,) noted that Russia possesses about 2,000 non-strategic nuclear warheads and added that its stockpile was likely to grow over the next decade:

Russia is adding new military capabilities to its existing stockpile of nonstrategic nuclear weapons, including those employable by ships, aircraft and ground forces. These nuclear warheads include theater- and tactical-range systems that Russia relies on to deter and defeat NATO or China in a conflict. Russia’s stockpile of non-strategic nuclear weapons (is) already large and diverse and is being modernized with an eye towards greater accuracy, longer ranges, and lower yields to suit their potential warfighting role.

General Ashley also noted, however, that due to Russia’s lack of transparency and the dual nature of delivery systems—incorporating conventional or nuclear weapons—estimates of Russia’s actual numbers of NSNW stockpiled or deployed are imperfect. As a 2020 report by the U.S. Congressional Research Service, which was updated in April 2022, it is unclear why Russia retains and may expand its stockpile of non-strategic nuclear weapons. Some contend that a larger and more diverse inventory of non-strategic nuclear weapons is Russia’s compensation for conventional forces that are inferior to those of the U.S. and NATO. Others see Russia’s non-strategic nuclear weapons modernization as contributing to an “escalate to de-escalate” nuclear doctrine that would require a wider spectrum of NSNW for coercive bargaining and war termination on terms favorable to Russia.

The Biden administration’s recently released Nuclear Posture Review also addresses the significance of non-strategic nuclear capabilities in U.S. and allied defense planning. In order to deter nuclear coercion and theater attacks, they plan to strengthen regional deterrence with capabilities such as the F-35A dual-capable fighter aircraft (DCA) equipped with the B-61-12 bomb; the W-76-2 warhead (low yield submarine launched ballistic missile warhead); and the Long-Range Standoff (LRSO) weapon. According to the NPR:

These flexible, tailorable capabilities are key to ensuring that Russia’s leadership does not miscalculate regarding the consequences of nuclear use on any scale, thereby reducing their confidence in both initiating conventional war against NATO and considering the employment of non-strategic nuclear weapons in such a conflict.

Despite this apparent consensus about the need to bolster U.S. and allied deterrence with additional non-strategic nuclear weapons, the place of NSNW in Russian strategy is more complex than the actual number of weapons available.

As scholar and military theorist Dmitri Adamsky points out, in terms of Russia’s ongoing war against Ukraine, its nuclear rhetoric is part of a “cross-domain coercion cocktail” intended as a means of strategic persuasion short of nuclear first use. Nuclear first use, if it occurs, is likely to have been preceded by muscle-flexing in the form of various “strategic gestures” (coercive signaling for deterrence and compellence) with nuclear forces to communicate the capability and resolve to climb the ladder of escalation. As he explains:

These “gestures” will be decisive enough to communicate credibility, but slow enough to allow the West to take notice of them, digest the information, and adjust accordingly. The Kremlin is unlikely to skip up the escalation stairs, but will advance through this phase incrementally to generate maximum effectiveness.

On the other hand, some experts rightfully caution that not every capability gap necessarily leads to a gap in deterrence or assurance. RAND Corporation analyst Edward Geist suggests that the resolve of U.S. decisionmakers prior to or during a crisis may be more important for deterring adversaries than the numbers and kinds of weapons available. According to Geist:

Not every deterrence or assurance gap can be remedied by acquiring more or better nuclear weapons. If adversary leaders scoff at the resolve of U.S. decisionmakers, even huge U.S. advantages in the number and quality of the United States’ nuclear weapons might not deter these leaders. Exaggerated rhetoric about ostensible adversary nuclear advantages could greatly enhance the danger of this outcome.