K-25 gaseous diffusion plant at Oak Ridge, one of the biggest engineering projects in history (Image: MPHPA)

Alex Wellerstein who is a historian of nuclear science has some cogent thoughts that feed into what has long since been a pet peeve of mine: the tendency for politicians, the media and scientists themselves to compare every large-scale government science or technology enterprise to the famed Manhattan Project. As Wellerstein demonstrates in his article, such a comparison is riddled with errors on many different levels, but that hardly stops even unlikely endeavors to elicit comparison with the sprawling atomic bomb project:

"It has become increasingly common to invoke the Manhattan Project as a general exemplar of applied science. Using Google’s Alert service, one can see that almost every week someone, somewhere, calls for a “new Manhattan Project.” Apparently, we need a Manhattan Project for cancer, for AIDS, for health, for solar power, for alternative energy, for fusion power, for thorium reactors, for global warming, for cybersecurity, for nutritional supplements (!), and, most literally, for protecting the island of Manhattan from the rising seas."

Wellerstein points out several reasons why the comparison is misguided, but here I want to focus on what I think is a very important difference purely on a technical basis, and one which is not always appreciated by the general public. The problem is that the Manhattan Project was a very specific kind of project done under very specific and very different circumstances, involving a level of government control, secrecy and expenditure that was unusual even for wartime. Flippant calls to turn other scientific projects into the Manhattan Project ignore the uniqueness and challenge of all these factors and risk misrepresenting important science projects in the modern era.

Here's what was different about building the atomic bomb: it was much more a feat of complex engineering than physics. Even Richard Feynman said this in his popular memoirs ("During the war, all science stopped except that involved in what came to be known as the Manhattan Project. And that was not really science, it was mostly engineering"). Physicists were undoubtedly crucial in working out the basic theory of fission, but the essentials of this theory had been worked out by the summer of 1942 or so, most notably in the Berkeley study. From then on it was quickly realized that the biggest obstacle in the project would be the separation and enrichment of uranium isotopes. This endeavor was regarded to be so difficult that even a visionary like Niels Bohr did not think it possible unless the entire United States were turned into one giant factory.

Ironically, they were. Detailed histories of the enterprise attest to the stupendous manual labor, resources - including a sizable fraction of the entire domestic supply of electricity and metals like copper and gold - and industrial construction and engineering that went into the building of the electromagnetic separation and gaseous diffusion plants at Oak Ridge, which when completed comprised the biggest factories under a single roof anywhere in the world. But most of this was engineering and project management; getting the giant calutrons to work, rigging up the intense magnetic fields and the electric supply, bringing chemical engineering and chemistry strategies to bear on separation of complex uranium compounds and reaction intermediates. In fact after engineering, chemistry rather than physics was probably the dominant science involved in the bulk of the Manhattan Project (chemistry and engineering were also involved on a large scale in plutonium production at Hanford in Washington state). One piece of evidence indicating that the project was mostly industrial engineering was its culmination in a military-industrial complex comprised of assembly line-like manufacturing facilities for nuclear weapons. And while we are on the topic, it's worth noting that the lionizing of physicists at the expense of engineers and chemists has also resulted in the neglect - in the public's imagination at least - of the one man who was truly indispensable to the project: General Leslie Groves.

It was at Los Alamos that physicists were most important, but even at Los Alamos the engineering challenges are often obscured by anecdotes about brilliant scientists like Oppenheimer, Fermi, Feynman and Bethe. In addition as Wellerstein documents, Los Alamos soaked up only 4% of the $2 billion spent on the project. Apart from the problem of uranium isotope separation, the second great problem that arose during the project was to figure out how to make the plutonium bomb work through implosion which was then a completely novel and unknown technique. Theorists like John von Neumann did make very important contributions to this problem, but again, after the theory was worked out the major challenge was in getting a perfectly symmetric implosion that would uniformly squeeze a ball of plutonium to supercriticality. This was a job for precision engineering and electronics. It was Harvard chemist George Kistiakowsky who brought precision explosives - then a startling concept since everybody only thought of using explosives to blow things apart - to bear on the challenge. The key endeavor in tackling the issue was the machining of explosive lenses and the invention of electronic fuses and circuitry that would ensure the instantaneous, symmetrical implosion of the assembly. This was again a challenge for electronics, mechanical engineering and chemistry rather than for physics.

In addition, unlike many modern projects to which it is compared, building the atomic bomb required collaboration between ivory tower scientists and dozens if not hundreds of industrial partners and engineering firms, including DuPont and Stone and Webster. DuPont especially played an invaluable role by building the plutonium production reactors at Hanford. Corporations also loomed large in the making of the first hydrogen bomb. Today it's much harder to imagine industry providing such extensive support to government projects, especially when the basic research arms of many once-prominent organizations like Bell Labs and IBM have been virtually obliterated and the parent companies themselves are struggling to thrive in a recession. Once again we see the unique collaboration between otherwise rather divergent research entities that can be engendered by the exigencies of wartime, a fortuitous circumstance that is unlikely to arise in the twenty-first century.

The summary of this foray into the details of the making of the bomb is to illustrate how the Manhattan Project was much more engineering and practical chemistry than pure science, how it was much more earthly project management than pie-in-the-sky thinking. It had a well-defined and rather well-understood goal and was therefore very far from the kind of pure scientific endeavors to which it is compared. This is especially true when it's compared to today's most high-profile Big Science project - the Brain Map initiative. Unlike the Manhattan Project, the purpose of endeavors like the brain map is to find out more about nature. Criticism of the initiative especially points to the paucity of our understanding of the human brain, a deficit that needs to be overcome if we are to launch any large-scale effort with well-defined goals. The real Manhattan project equivalent of the Brain Map project would not be the construction of an actual bomb but a foray into understanding the properties of atoms and nuclei, something that was accomplished very well by Small Science in the 1930s and would have been hard to contemplate if it had been cast under the umbrella of a tightly controlled military project enveloped in secrecy and kowtowing to a specific goal. It was only after a reasonable understanding of nuclear physics was accomplished that the properties of the atom could be put into the service of the creation of a weapon of mass destruction.

As Wellerstein nicely points out, there are other problems in comparing the project to modern day science enterprises, including the extreme secrecy imposed on the project and the moral ambiguity that resulted from its success. But the point of my post is to make it clear that even on a strictly technical level, the Manhattan Project was very different from any other Big Science project to which it is compared. So was the Apollo moon shot, another enterprise steeped in engineering and virtually removed from pure science, both in its methods and in its fruits. The Manhattan project was indeed a miracle of science, engineering, government initiative and academic-industrial coordination. But while we can certainly learn specific lessons from it, what we need is a new project for a new era. With a different name.

Some useful references:

1. The Making of the Atomic Bomb - Richard Rhodes.

2. Critical Assembly - Lillian Hoddeson.

3. Racing for the Bomb - Robert Norris.

4. A Chemist in the White House - Glenn Seaborg.