While the nuclear weapons used in World War II were forged by scientists seeking to make a thing never before seen, the scientific way of thinking is insufficient for the job of stewarding the nuclear bomb. For that job, you need engineers. The engineer’s job to democratize the fruits of the scientists’ labor. The engineer takes scientific discoveries and incorporates them within a framework of established standards to create practical systems that can be used in a clearly marked domain. A proper understanding of this work is important for good policymaking – whether you believe the country should develop new nuclear weapons or totally eliminate them. Engineering helps create an extremely wide array of systems, and the demands of nuclear weapons system designs have sparked innovations that revolutionized the broader community of engineering. Take, for example, the rolamite, an extremely low-friction bearing developed in the 1960s by a mechanical engineer in the national labs complex. The component’s extreme precision enabled lab engineers to give nuclear weapons a sort of sentience to discriminate whether or not proper authorization to complete their explosive mission had been given. Since the rolamite was invented on the government dime, its design was freely available to the public, and it quickly found a wide array of applications in other devices (its ability to reliably distinguish between a collision and a hard braking stop made it the sensor of choice for triggering airbags in automobiles). This is just one item in a portfolio of innovations that the Nuclear Enterprise inspired. The high demands of reliability required by nuclear weapons systems has pushed the engineering discipline into new territory, transforming paradigms and sparking innovations that no other set of problems had been able to produce. Engineering innovations have been crucial in international diplomatic agreements as well. The NATO double-track decision of the late 1970’s ultimately put US-Soviet relations on a footing that enabled the Intermediate-range Nuclear Forces (INF) treaty to be signed, directly leading to a major de-escalation of bilateral tensions and the elimination of some 2,692 nuclear warhead and an entire class of weapons. The agreement would not have been possible but for engineering developments that produced ballistic guidance and earth penetration technology on the Pershing II missile. The military capability enabled by this system brought strategic stability to the Cold War rivals and made the signing of the INF treaty an appealing prospect for both sides. This experience highlighted the ability of a well-established engineering enterprise to facilitate the reduction of international tensions. An understanding of what engineers do, and don’t do, is crucial to healthy debates about nuclear policy. Whether your view of the stockpile is that it should be modernized, maintained, reduced, or even eliminated, any vision of the future of nuclear weapons is only as good as the practical engineering considerations that go into it. If you believe that the stockpile should incorporate new systems that can provide political and military leaders a more agile response to future threats for the sake of strategic stability, but haven’t considered the time and cost necessary to develop and produce them, your policy arguments will be weak. Likewise, if you aspire to a diminished stockpile that holds less destructive force, but dismiss the value of the engineering resources invested in the nuclear enterprise and the impact they have on geopolitics, your arguments may be called imprudent. Sensible policy aspirations must balance aspirational visions of the future with a clear understanding of the cost and value of the nuclear weapons engineering enterprise.