The Need for Non-Strategic Nuclear Weapon Systems: The NPR Got It Right

The Nuclear Posture Review (NPR) released last month called for the development of a new low yield warhead and new delivery systems to address shortfalls in existing deterrent capabilities.  It proposed that a present capability, dual-capable aircraft, to deliver low-yield nuclear weapons be augmented by the development of a low-yield ballistic missile.  For sea-based weapons, the NPR called for using existing D-5s to carry a modified, lower-yield W-76 nuclear warhead within the next few years, and a new sea-launched cruise missile added in the 2030 timeframe.  These capabilities are sought to address current limitations in the U.S. non-strategic force posture in the face of potential Russian aggression against NATO. 

The low-yield capabilities identified by the NPR are needed by the United States for six reasons. First, non-strategic nuclear weapons provide a deterrent by denial capability.  Deterrence by denial centers on the ability of the defender to deny territorial gains to the enemy, in contrast to deterrence by punishment, which centers on the threat and capacity to inflict nuclear punishment.  Denial capabilities—typically, conventional ground, sea, and tactical air forces—deter chiefly by their effect on the aggressor’s calculus.  They adversely influence the enemy’s estimate of the probability of gaining the objective. Any conventional attack would be met with non-strategic nuclear forces to blunt the attack, and thus deny the attacker its military objective. Due to their physical effects, non-strategic nuclear weapons are seen as being exceptional deterrence by denial weapons.  They were used in that capacity by the United States and the Soviet Union during the Cold War, and this rationale remains.

Naturally, another aspect of deterrence is to keep the enemy from using its weapons, whether they are conventional or nuclear. Accordingly, the second political and military role played by non-strategic nuclear weapons is that they serve to deter their use by opponents.  But to do so is challenging, U.S. non-strategic weapons must be present in sufficient numbers and on survivable platforms.

Third, should deterrence fail, non-strategic nuclear weapons are perceived as the most “useable” of nuclear weapons due to their low yield, which would augment conventional forces in stopping an attack on land, at sea, in the air, or destroying targets too hardened for conventional weapons.  Their low yield would also permit limited escalation against a higher-level target set, such as Russian leadership targets, to compel termination. 

Fourth, non-strategic nuclear weapons served an important doctrinal role for NATO armies today, as they did in the Cold War. They bridge the nuclear-conventional interface, maintaining linkage up the ladder of escalation. Were a conventional attack to occur, NATO would want the capabilities to use non-strategic nuclear weapons to defeat it, should conventional weapons fail to do so. This mission overlaps to some degree with deterrence by denial since NATO would want to deter such an attack in the first instance. However, should conventional weapons be unable to stop the attack, NATO would escalate and resort to a nuclear “signal,” or the limited use of non-strategic nuclear weapons to arrest the attack. If low-yield nuclear weapons failed to halt the attack, then escalation to the strategic level would be a possibility. In this manner, conventional weapons, non-strategic nuclear weapons, and strategic nuclear weapons use would be “coupled” together, with a clear military logic dictating escalation to the next level. Thus, non-strategic nuclear weapons serve an important role as the likely connecting tissue between conventional and strategic nuclear forces.

Fifth, non-strategic nuclear weapons serve as a powerful and costly political symbol of the United States extended deterrent commitment to NATO allies. Non-strategic nuclear weapons serve the grand strategic role of the political “coupling” of the alliance members in two major ways. First, major European states are linked together by hosting the weapons, by the possibility of their use, and through nuclear planning within NATO. Thus, there is shared responsibility and risk, which in turn signals commitment to the alliance. Second, the United States is coupled with its NATO allies by virtue of their deployment to Europe and the United States commitment to their use should deterrence fail, and if the foe is unable to be stopped at a lower level of conflict.  Born of the Cold War, the political role of non-strategic nuclear weapons for the NATO alliance remains important.

Sixth, non-strategic nuclear weapons will also have a role in strengthening the ability of the U.S. to coerce its opponents, should that be necessary.  This capability is particularly important concerning China.  Over many years now, China has acted against U.S. interests, and indicated that it is not a status quo power but seeks substantial changes to the present international order.  Its expansion in the South China Sea has gone unchecked, and this has had profound and unnerving effects on U.S. interests, its allies, and other states in the region.  It may be necessary to use U.S. power to compel China to change its posture.  U.S. non-strategic capabilities are insufficient to meet immediate and likely strategic requirements against China and Russia.  Thus, it is essential that the small number of non-strategic weapons in the U.S. arsenal need to be augmented by the NPR’s proposed systems.

Chinese and Russian non-strategic and strategic capabilities continue to grow, and China continues to expand in the South China Sea, build bases in Africa and the Indian littoral while challenging the position of the U.S. in global politics.  The United States needs the expanded capabilities illuminated in the NPR as soon as possible to meet these considerable challenges.  The roles of non-strategic nuclear weapons are many, and the United States needs to possess an arsenal suitable to the reality of contemporary international politics where both Russia and China are hostile to its interests. 

Bradley A. Thayer, P.hD., is the author, with John M. Friend, of the forthcoming How China Sees the World:  The Rise of Han-Centrism and the Balance of Power in International Politics.