“Sole purpose” also would make a shamble of U.S. extended nuclear deterrence commitments to U.S. allies—for example, the U.S. promise to extend nuclear-deterrence coverage to assure allies of their security. The downsides of so destroying this U.S. promise are many, but perhaps most notable is the possible wave of nuclear proliferation it would unleash as allies and partners feel compelled to find alternatives to U.S. nuclear-deterrence protection. Such minimum-deterrence policies could actually work to spur nuclear proliferation.       

Next, minimum-deterrence proponents typically claim that further deep reductions in U.S. nuclear forces would indeed save billions of dollars and are necessary to strengthen U.S. nonproliferation efforts worldwide. But the claim of great savings is likely vapid, because minimum-deterrence proponents tell only half the story. The corresponding needed expansion of U.S. conventional forces recommended by proponents to help sustain deterrence would likely cost much more than any savings realized from further deep cuts in U.S. nuclear forces. One of the major and long-recognized advantages of nuclear forces over conventional forces is that they are comparatively cheap. NATO learned this lesson early in its history, which is why NATO was and seeks to remain a nuclear-armed alliance. Russia has discovered this fact, too, which is one reason why it is committed to new nuclear-force programs. The truth is that moving to a much greater emphasis on conventional forces for deterring enemies and assuring allies, if practicable in principle, would not save defense dollars; it would be extremely costly. In an era of U.S. defense spending austerity, the claim of great savings via deep nuclear reductions is a particularly pernicious sleight-of-hand.

In addition, as already noted, minimum-deterrence policies could easily lead some allies and partners to reconsider their non-nuclear status, and the available evidence does not support the notion that exemplary U.S. deep nuclear reductions would lead other states to mimic U.S. behavior. The available evidence on this score, limited as it is, suggests that the reverse may be true—possibly because potential opponents do not seek nuclear weapons in mimicry of U.S. nuclear policies in the first place. They do so in large measure to address perceived security threats, including the U.S. conventional-force advantages that minimum-deterrence proponents want to emphasize.           

Finally, what of the frequent minimum-deterrence assertion that reducing the number of nuclear weapons will reduce the probability of accidents? Even a cursory look at official and unofficial sources shows this claim to be contrary of available evidence. In the years 1950, 1964 and 1982, the United States experienced the same number of accidents in its nuclear force (for example, five). Yet the United States had vastly different arsenal sizes at those times, approximately 300, 29,000 and 23,000, respectively. During the Cold War, the United States experienced a peak of twenty accidents in 1958, when the U.S. arsenal had about 7,300 weapons—well below the historic high point of 31,000 weapons in 1967, a year in which the United States experienced five accidents. In essence, the United States experienced four times as many accidents in 1958 when it possessed less than a quarter of the 1967 arsenal size. In short, available data shows no positive correlation between the size of the U.S. nuclear force and the number of accidents. There is strong evidence that the same holds true for at least some other nuclear powers. The data shows that the number of accidents has been independent of force size.

There is some evidence of the context that can contribute to nuclear dangers. The recently released Independent Review of the Department of Defense Nuclear Enterprise, headed by retired General Larry Welch and Admiral John Harvey, notes that the men and women of the U.S. nuclear forces, “are well aware of the public declarations by former (and, occasionally, current) senior national security leaders and others who question or deny the continuing relevance of the nuclear forces or segments of the nuclear forces.” This perception, they conclude, has contributed to a decline in morale, job satisfaction and performance by the stewards of the arsenal. Ironically, minimum-deterrence language discounting the relevance and value of the U.S. nuclear arsenal may in fact contribute to a context that increases the prospect for nuclear mishaps.

In summary, not a single main argument of the minimum-deterrence narrative is solid, and much of it is demonstrably false. The fact that Democratic and Republican administrations have largely withstood minimum-deterrence advocacy for five decades is a reflection both of welcome prudence in Washington and the banality of the minimum-deterrence narrative.

Keith B. Payne is the director of the Graduate School of Defense and Strategic Studies at Missouri State University and a former deputy assistant secretary of defense. Matthew Costlow is an analyst at National Institute for Public Policy.

Image: Flickr/International Campaign to Abolish Nuclear Weapons/CC by-nc 2.0