Both of these volumes address well-known subjects dealing with the horizontal and vertical proliferation of nuclear weapons. Rupal Mehta’s monograph explores the role played by US military threats, sanctions, and inducements in prompting governments to abandon efforts to develop nuclear weapons, whereas Ken Young and Warner Schilling delve into the policy debates and infighting prompted by the Harry S. Truman administration’s decision to develop a fusion weapon, which was sometimes referred to as the “Super” in the 1940s and early 1950s. When juxtaposed, the two volumes illustrate the complexity, irrationality, and even the inevitability of governmental decisions related to nuclear acquisition.

Mehta advances an explanation for how outside influence can create the conditions for nuclear “reversal”: the decision to abandon a nascent nuclear weapons program. As her statistical analysis illustrates, such decisions are actually quite common. More than two-thirds of would-be proliferators have abandoned their quests to develop nuclear weapons or their nuclear arsenal. Mehta’s theory focuses on US policy as the key element of international nonproliferation efforts: if the United States offers inducements, threatens sanctions, and can credibly point to the prospect of military action to destroy nuclear facilities or even change regimes, then governments, especially those that have recently acquired new leadership, are likely to reassess their aspirations for acquiring nuclear weapons. Mehta emphasizes that the threat of sanctions alone is not enough to prompt governments to reevaluate the desirability of pursuing a nuclear arsenal.

Mehta’s explanation of counterproliferation success and failure is logical and reasonable; ceteris paribus, the US policies and international conditions she identifies should move targeted governments to the side of the angels. Nevertheless, the events she surveys vary widely, and it is difficult for her inductive theory to account for all outcomes, especially for a number of successful reversal cases. For instance, the end of nuclear programs in several important countries in her database (e.g., Canada, Italy, Japan, Norway, and West Germany) involved the extension of formal US nuclear security guarantees, whereas others (e.g., Sweden, Switzerland, Taiwan, and South Korea) involved a more informal security relationship with the United States. In other words, the formal or implied US offer of a “nuclear umbrella” might account for much of the variation she encounters in her dataset. One could also add that if military threats were included in the US approach to these would-be proliferators, those threats were veiled indeed.

Mehta admits that the variables and conditions she identifies really are not necessary or sufficient to cause reversal decisions on the part of targeted governments, despite the fact that some regimes—Muammer al-Qaddafi’s Libya is a case in point—are prompted to abandon their nuclear aspirations when confronted with the mélange of international threats and inducements identified by her theory. Nevertheless, sometimes similar policy efforts and conditions fail to move a target toward reversal. The Trump administration’s overture to a new North Korean leader, Kim Jong-un, which actually constitutes a somewhat unconventional approximation of the normative elements of her theory, failed to induce Pyongyang to abandon its nuclear arsenal. Against determined and capable targets—France, India or the People’s Republic of China—US policies constitute little more than a speed bump on the quest to acquire a nuclear weapon.

Young and Schilling explore the other side of the proliferation picture by identifying the participants and their policy positions comprising the nasty battle over the decision to develop the hydrogen bomb. The “back story” behind their book, however, highlights why it constitutes a unique contribution to the historical literature and to our understanding of bureaucratic politics: it uses a theoretical approach to explaining foreign and defense policy formulation and international behavior that has faded from popularity over the decades. Neither Young nor Schilling lived long enough to see their book completed, and Schilling had passed before it was even started. Nevertheless, the manuscript incorporates the results of scores of interviews Schilling conducted in the late 1950s with all of the key participants in the debate, from Truman to Robert Oppenheimer to Edward Teller to staff members of key congressional committees. Undertaken while emotions still ran high and most of the Cold War lay in the future, the interviews were not tainted by the hindsight we enjoy that makes development of the Super appear politically, strategically, and technologically inevitable. Sixty years of gestation makes Super Bomb a unique book and, intellectually speaking, an interesting archaeological find.

As a case study in foreign and defense policy formulation, Super Bomb has the feel of the “first wave” of the bureaucratic politics literature, to use a term first introduced by Robert Art. With the advent of so-called service unification that was mandated by the National Security Act of 1947 and the exponential increase in the size and complexity of the US military establishment during World War II, scholars became interested in the posturing and infighting within the executive branch over policy issues, especially issues related to service missions and budgets. Young and Schilling trace how individuals from different organizations adopted different positions on the development of the Super, which to a certain extent coincided with the mission and budgetary interest of their home agency. Air Force officers, especially those associated with the Strategic Air Command, championed development of the Super, associated heavy bombers, and the strategy of countervalue targeting as an appropriate deterrent of Soviet aggression—a position that corresponded to their strategic vision and the budgetary health of their newly created service. Navy officers stated that development of the Super and the adoption of countervalue targeting were immoral, which led to the classic comment offered by an Air Force general that was recorded by Schilling in one of his interviews: “an immoral weapon is one that is too big for your service to deliver.” Teller saw the issue as a way to create a healthy nuclear competition between Oppenheimer at Los Alamos and himself and the physicists located at Berkeley, whereas many holdovers from the Manhattan project saw the Super as a weapon that would simply lead to Armageddon.

Young and Schilling offer an insightful and somewhat unsettling view of the nature of bureaucratic debate, something not quite captured by such euphemisms as “interagency process” or “policy coordination.” Debate becomes ad hominem and visceral: attacking the credibility, loyalty, and character of a policy opponent can be more effective than attacking the logic or facts behind their position. When Oppenheimer suggested that the development of fusion weapons might interfere with the development of advanced “boosted” fission weapons and the creation of a tactical nuclear arsenal suitable for battlefield employment, and that the development of a working air defense system might be a better way to protect the United States than the Strategic Air Command’s planned “city-busting” campaign, his loyalty and motives were called into question by those in favor of the Super. Nevertheless, Oppenheimer also was horrified by the immorality and insanity of using fusion weapons to destroy an opponent’s urban-industrial base as a preferred wartime strategy, leaving his policy opponents to ponder whether Oppenheimer’s advocacy of tactical nuclear weapons and air defenses was just a bureaucratic subterfuge to satisfy his moral objections to the Super. Fission weapons might have possessed more military utility and cost effectiveness at the margins than fusion weapons, but no one volunteered a strategic “cost-benefit” analysis to evaluate these competing approaches “to living in a world in which the Soviets possessed a nuclear weapon,” to borrow one of Schilling’s favorite phrases.

Young and Schilling also illustrate why the counterproliferation efforts surveyed by Mehta are so difficult. US development of the Super was more or less inevitable, barring some breakthrough in global nonproliferation efforts, a fundamental transformation of the Soviet government, or the rejection of its worldview colored by Marxist-Leninist ideology. Despite the fact that this state of affairs was more or less apparent to the participants at the time, there were individuals and agencies in the US government who had a personal or bureaucratic interest in not moving forward with the development of the hydrogen bomb. A different, albeit significantly altered, international setting might have allowed those who championed a halt to vertical proliferation to hold sway, although the accumulation of counterfactual developments in this alternative historical narrative strain credulity. For states with a marginal interest and few resources to devote to a nuclear program, it might be easy to alter the internal policy balance favoring acquisition of a nuclear arsenal. Nevertheless, when states possess the resources and perceive significant incentives to acquire a nuclear arsenal, it might be beyond the ability of the United States to alter the international setting to allow “nuclear dissenters” to reverse a government’s quest to acquire a nuclear arsenal.