Continuity and Change in U.S. Nuclear Policy
In recent decades, each new President, early in his first term, has conducted a wide-ranging review of U.S. nuclear policies, posture, and programs.
Each of us, serving Presidents from both parties, have led in developing and implementing policy for one or more of the four reviews completed since the Cold War’s end (Clinton in 1994, Bush in 2001, Obama in 2010 and now Trump in 2018).
Each of us considers the 2018 Nuclear Posture Review (NPR) recently issued by Secretary of Defense Mattis to be clearly in the mainstream of U.S. nuclear policy as it has evolved through nearly eight decades of the nuclear age.
The 2018 NPR reflects much more continuity than change. It affirms the necessity of a strategic Triad of land- and sea-based missiles and bombers, along with European basing of U.S. nuclear bombs carried by NATO aircraft. These capabilities provide the basis for deterring war and assuring threatened allies of continued U.S. commitments to their security.
The 2018 NPR affirms that deterrence cannot be based solely on the existence of U.S. nuclear forces but, rather, on their ability to hold at risk assets most valued by adversaries. Thus, U.S. force numbers and capabilities matter, and may need adjustment as deterrence requirements change over time with shifting adversaries and threats.
It affirms that the U.S. must maintain a nuclear weapons enterprise capable of responding promptly to unanticipated technical problems with warheads or delivery systems, or to adverse geopolitical change.
The 2018 NPR, as did previous reviews, continues the moratorium on nuclear weapons tests, reiterates traditional negative security assurances, and promises to abide by the limits on nuclear forces established in arms control agreements—provided that Russia adheres to those limits as well. Indeed, it affirms an intention to work with Russia to reduce nuclear dangers, when and if Russia is prepared to work with the U.S. to that end.
The 2018 NPR affirms long-standing policy that deterring a nuclear attack is the primary but not the sole purpose for U.S. nuclear weapons. In doing so, it does not expand the role of nuclear weapons but clarifies that role in deterring “non-nuclear strategic attacks” including adversary use of biological weapons, or an assault on critical national infrastructure, leading to mass U.S. or allied casualties approximating those inflicted by a major nuclear strike. The American people would not seek to take any military option off the table in responding to such a catastrophic attack.
Over decades, these basic tenets of nuclear policy affirmed by the 2018 NPR have garnered broad bipartisan support, notwithstanding spirited debate on the details.
Proposed changes to the U.S. posture in the 2018 NPR are modest and follow with substantial changes in global security since the 2010 report. These include, most importantly Russia’s open contempt for the European security order, use of force to change borders as in the occupation of Crimea, nuclear first use threats to U.S. allies, decade-long modernization of nuclear weapons, continuing violation of the Intermediate-Range Nuclear Forces (INF) Treaty, and the surging role of nuclear weapons in Russia’s security posture.
Russia’s nuclear strategy envisions limited first use of nuclear weapons in an ongoing conventional conflict with NATO as a means to end that conflict on terms favorable to Moscow. Some call this an “escalate to win” strategy. It is reflected in recent Russian doctrine and military exercises, and in Russia’s ongoing modernization programs for tactical nuclear weapons. Russia’s leaders seem to believe that Moscow could engage in nuclear first-use without undue risk. The U.S. must work to correct such dangerous and destabilizing beliefs.
The existing mix of U.S. capabilities, although quite robust, has not inhibited this Russian nuclear assertiveness. As a result, the 2018 review advanced two initiatives: (1) a low explosive yield option for submarine-launched ballistic missiles (SLBM), and (2) the restoration of nuclear, sea-launched cruise missiles (SLCM). In complementing other U.S. nuclear capabilities, these initiatives convey a message that any use of nuclear weapons would provide Moscow with no advantage, only unacceptable consequences. That is the essence of deterrence.
Opponents argue that a low-yield SLBM warhead will be “new,” costly, and dangerous (by lowering the nuclear use threshold making nuclear war more likely). Not so. These weapons would raise the bar to limited first use by convincing Russia that the risks of such use far outweigh any possible security benefit. Moreover, this capability is not new and could be achieved with a small, relatively low-cost modification to an existing warhead without requiring underground nuclear tests.
Restoration of nuclear SLCMs (retired in 2010) serves two other purposes. SLCM poses a security cost and hence provides Russia a significant incentive to return to compliance. Were it to do so, the U.S. has the option to simply halt the SLCM program.
Second, SLCM strengthens assurance of both European and Asian allies. Japan and South Korea, who have reacted strongly to North Korea’s nuclear tests and missile launches, would value a routine U.S. nuclear presence in the region as a signal of U.S. resolve. SLCM achieves this without requiring overseas land-basing of U.S. nuclear warheads, the debate on which could be disruptive to allied publics.
Importantly, the 2018 NPR carries forward the program begun in the Obama administration to replace nuclear forces that have aged well beyond the end of their planned service lives, and to rebuild aging warhead production infrastructure, some of which dates to the 1940s Manhattan Project. This program has been criticized as unaffordable. At the peak of this modernization cycle, however, nuclear forces and nuclear command and control will consume less than 7% of the annual defense budget, declining to 3% as modernization winds down, well below the investment levels of earlier modernization cycles. As Secretary Mattis has said, “we can afford survival.”
The 2018 NPR is consistent with what has gone before. It is a prudent, modest, update of U.S. posture that will keep America and its allies safe. It deserves bipartisan support.
The authors have among them decades of experience serving in senior posts in the U.S. government overseeing nuclear weapons policies and programs, Harvey in the Departments of Defense and Energy, Miller in the Department of Defense and the NSC Staff, and Payne and Roberts in the Department of Defense.