The 2023 Strategic Posture Commission rightfully called attention to US strategic force deficiencies and a renewed emphasis on nuclear deterrence. The security dilemma is not like it was between the US and the Soviet Union during the Cold War. It is worse. In a tripolar world of nuclear peers where the US faces simultaneous armed conflict with Russia and China, a significant imbalance of forces has led to an asymmetry of nuclear strategy.
Key disparities in nonstrategic nuclear forces following decades of arms reductions now jeopardize American nuclear strategy. To resolve this, a rebalance of “theater-strategic” nuclear forces is needed for the US to credibly prevent conflict and dangerous escalation, uphold extended-deterrence guarantees, and avoid failure of central deterrence.
America’s adversaries are expanding their nuclear arsenals, including tactical, regional, theater, and strategic forces. For example, China already has multiple air-, land-, and sea-delivered systems deployed to counter the American military. In Europe, the US and North Atlantic Treaty Organization (NATO) member-states are outnumbered 10-to-1 against Russia in such systems, and only possess small numbers of tactical gravity bombs delivered by limited-range fighter aircraft.
Adversaries can target American forward-deployed forces, US territories, and the American homeland. Further, the homeland is now outnumbered in the number of deployed strategic nuclear weapons, and this disparity is projected to reach 2-to-1 soon. With a weak tactical, theater, and strategic nuclear position, the US faces new threats by emboldened and unafraid adversaries.
The first problem with this asymmetry of nuclear strategy is that Russian or Chinese leadership may believe they have escalation advantage over the US during a regional conflict. Adversary nuclear forces employed early on the battlefield with the threat of incremental employment and with less escalatory short-range delivery systems would place the “burden of escalation” upon the United States. With each missile system of varying range, threatening attacks against targets of graduated value and stake to the US, the only retaliatory tool available to the US with sufficient power to create deterrent or compellent psychological effects is its intercontinental-range nuclear triad.
Chinese or Russian leaders may view such an American choice to be highly escalatory, triggering further nuclear escalation. Just as worrying, adversary leaders may well believe that once this “burden of escalation” is placed on the shoulders of the president, it would create such fear of uncontrolled nuclear escalation that the US will capitulate instead of choosing to escalate further. Current American nuclear capabilities provide very limited options to the president for battlefield objectives while managing escalation in conflict.
A second problem is extended-deterrence credibility. This security guarantee is for over 30 allies in Europe and Asia and involves American threats of nuclear retaliation against adversaries that attack the nation’s allies. Deterrence is “extended” to allies under the “nuclear umbrella.” However, for extended deterrence to be credible, American nuclear forces must be capable of defeating adversary threats to those allies. But this presents a problem because nuclear-armed adversaries possess the advantage in low-yield, short-, medium-, and intermediate-range nuclear force.
For American extended-deterrence credibility, the US requires damage-limitation capabilities for the homeland. Otherwise, the nation risks becoming “decoupled” from its allies in regional conflicts. This would place the adversary in a superior position to coerce American allies into submission under threat of nuclear attack. The US could credibly prevent decoupling through offensive forces that can destroy adversary nuclear capabilities capable of striking the homeland and through homeland missile defenses after adversary attacks.
However, US offensive damage-limitation strike capabilities cannot credibly target all Russian and Chinese strategic nuclear forces simultaneously. Further, US homeland missile defenses are deployed to limit damage primarily from states like North Korea, whereas the US relies on deterrence to address Russian and Chinese intercontinental-range nuclear missile threats to the US homeland. As a result, the ability of the US to credibly limit damage, avoid decoupling, and fulfill its extended-deterrence security guarantees is currently limited, and the disparity in American and adversary forces is also projected to widen.
The third principal reason the asymmetry of nuclear strategy is becoming increasingly problematic is the risk of effective adversary coercion directly against the US in a regional crisis or armed conflict. “Central deterrence,” or persuading adversaries from carrying out intercontinental nuclear strikes against the homeland, could be severely challenged should a regional war and threats of nuclear escalation overwhelm an American president faced with choices involving catastrophic attacks on the homeland.
Russia and China now possess sufficient operational and theater nuclear forces to convince their leaderships they hold escalation advantage over the United States. This would place the US president “on the horns of a dilemma,” choosing to fight a regional war against one or more nuclear-armed adversaries who possess battlefield and theater-nuclear escalation advantages over the US or choosing survival under conditions of nuclear coercion and regional capitulation. This is the exact opposite of where the US should be positioned to fulfill its nuclear strategy obligations and defend the nation and its allies.
An American theater-strategic nuclear force rebalancing recognizes the interplay between theater and strategic risks. If the US cannot meet its battlefield war aims or perform extended deterrence effectively, then it increases the risks of attack or escalation on the homeland. Such risks increase with simultaneous conflict and escalation with Russia and China.
The US needs to field low-yield air-, ground-, and sea-based theater nuclear forces in both the Pacific and Europe. For operational and psychological reasons, such forces should reflect the attributes of the strategic-level nuclear triad (responsive, flexible, survivable), giving the president a wide set of options and credible power.
The president also needs a substantially more robust strategic nuclear triad to simultaneously threaten the full range of homeland targets of value to Russia and China, including their entire fixed and mobile nuclear force. Critically, the president also needs assurances that the homeland can be defended against coercive decapitation or population center strikes.
Nuclear threats are rising and the challenge to security surpasses what a fully modernized nuclear triad can reasonably expect to provide. A modern nuclear triad is essential; it is just not enough. Rebalancing US nuclear and missile defense forces is needed to restore symmetry in nuclear strategy and establish strategic stability in the tripolar world.
Dr. Jonathan Trexel is a graduate faculty member with Missouri State University’s School of Defense and Strategic Studies and a Senior Fellow at the National Institute for Deterrence Studies. The views expressed in this article are the author’s own.
A must read piece on a critical problem: America’s weakness in in-kind proportionate retaliation against adversary low-yield attacks, compromising our ability to deflect coercion, deter attacks, and credibly assure allies. Short of somehow rapidly building up our in-theater tactical nuclear forces to rough parity with Russia and China — despite White House antipathy — exactly as the author strongly (and RIGHTLY) urges, what options would POTUS have IF Putin or Xi suddenly nuked one of our nuclear umbrella allies? Methinks these include: 1) give in to the geopolitical coercion [Unacceptable!] , 2) retaliate with a high-yield weapon [NOT proportionate], 3) retaliate with conventional weapons [might work against a “clean super-low-yield mini-nuke], or 4) retaliate with our own low-yield weapons while the supply lasts, then improvise more by removing the lithium hydride from some stockpiled H-bombs. I vote for Option 4, which calls for planning, training, exercising, and forward deploying NOW…. Trexel also clearly articulates the importance of an effective counterforce triad and reliable, rightsized BMD, to protect the homeland and also put backbone in our extended deterrence assurances…. A solid, thought provoking treatment.