17 November 2008

The Manhattan Project

Please stop using the term "Manhattan Project" to refer to a government-funded project to develop a desired technology.

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The original Manhattan Project was initiated by the US government in July 1941 in response to the MAUD report, a study commissioned by the National Defense Research Committee liaison office (UK) to establish the feasibility of a nuclear bomb. The MAUD report established that, not only was such a bomb immanently possible, it was probable that the Third Reich was working on one of their own.1 Prior to this, the (US) National Academy of Sciences had taken a skeptical view of nuclear ordnance.

Vannevar Bush was able to persuade the Roosevelt Administration to launch a new, specialized agency for R&D into the nuclear bomb (November 1941). With the attack on Pearl Harbor a month later, everything was greatly accelerated. The original program to actually develop a working uranium bomb was set up in Syracuse, New York and later in New York City. Hence, it was called the "Manhattan Engineering District" (MED

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) instead of anything referring to its function. The MED was administered by the Army Corps of Engineers and included researchers from the UK and Canada as well as US nationals.

By 17 September '42 the MED was under the management of Brig. Gen. Leslie Groves, and in Oak Ridge, TN. Groves was responsible for logistics, while J.R. Oppenheimer was responsible for scientific research. A major time constraint for the production was the production of an adequate stock of fissile U235, which required three different facilities using different methods to produce.2 The Manhattan Project quickly focused on two main design strategies: a uranium design, which would blast a cork-shaped mass of uranium into another mass of uranium in order to trigger a nuclear explosion; and a plutonium design, in which a spherical mas of P239 was enclosed in a larger sphere of explosives. The later design was more technically demanding because of the need for extremely precise coordination of the explosive "tiles" encasing the plutonium.

The explosion created by the two bombs virtually eradicated the urban centers of their respective targets, Hiroshima and Nagasaki. The "little boy" bomb used on Hiroshima (7 August) had an explosive force of 15,000 tons of TNT, and probably killed about 70,000 people in the initial blast. In the years that followed, the combination of burns and radiation poisoning may brought the death toll up to 200,000.3 The other bomb, "fat man," had a yield of 22,000 tons TNT and was used against the city of Nagasaki. This city was smaller and the death toll was somewhat lower.

There remains a firestorm of controversy over the necessity or morality of the use of the atom bombs on Japan. I've been disappointed by the way the issue has been generally exploited by partisans to support opinions on other subjects—a football, so to speak, in an ongoing propaganda war. As an amateur student of history, I personally have learned that it's vain and self-deceiving to make judgments on these matters because one cannot (or will not) ever make a valid reconstruction of the understanding historical actors had of the events in which they acted. (I am well aware of the fact that many people will think this is somehow immoral, as if I'm somehow evading a great moral test.) But this is a bit far afield from my original subject.

UPDATE: My views on the ethics of the A-bomb use.

The Manhattan Project emerged from under this avalanche of history as the prototypical project to use a massive drive to develop a "magic bullet," a technology that would end the War. Somehow, that technology has been divorced from any context. I guess people want to conjure up the amazing technical feat of not only achieving a nuclear bomb in only three years, but achieving the first nuclear bomb in only three years; and applying this to some unknown new technology, similar to the A-bomb in its revolutionary character, but reversing the moral polarity. People have been calling for a Manhattan Project to develop competitive products, or resolve our dependence on fossil fuels, or even resolve our financial crisis.

But any such program would have to incorporate the Japanese anyway; their control of trillions of Eurodollars plus their mammoth technical skills make them indispensable. Moreover, there is something basically insidious about the whole idea of a technology, divorced from economic or political context, actually solving anything. I would argue that the A-bomb was an inherently bad technology, like torture: even if it might potentially have "worked" one time, its existence tended to corrode democratic values and basic principles of just war. It was developed in the absence of any serious consideration of what its use would do to the concept of democracy or "legitimate use of force," and as such it inevitably undid any short-run advantage gotten by its first use.


1 "The Manhattan Project: an Interactive History," Department of Energy website. Vannevar Bush was the founder and director of the Office of Scientific Research and Development (OSRD), a wartime agency.

2 "The Manhattan Project: an Interactive History,"Ibid. Uranium atoms have 92 protons and 92 electrons, but anywhere from 125 to 150 neutrons (an isotope of an atom is a "version" of that atom distinguished by a particular number of protons + neutrons). The vast majority of uranium isotopes have a tendency to "decay" into something else within a microsecond or less. We call an isotope "stable" when it has a half-life measured in years, and there are six of these for uranium. The most common one that can sustain a chain reaction is U235 (92 protons + 143 neutrons); this accounts for about 0.7% of all uranium found in nature. However, about 99.3% is U238, which has an additional three neutrons. U238 cannot sustain a chain reaction, and must be refined away from an available crucible in order to produce "weapons grade" uranium (>80% U235). This is an extremely costly and difficult process, and it is astonishing that the US government was able to organize a successful extraction regime in less than three years.

Plutonium is an artificial substance that does not exist in nature. There are twenty isotopes, but the one primarily used for nuclear weapons is Pu239. Plutonium is synthesized from uranium in a specially-designed reactor and refined from the residue that forms in a nuclear reactor fuel rod.

3 "The Atomic Bombing of Hiroshima," Ibid. Many readers will object that I'm citing Department of Energy information, since the DOE is an arm of the same government that carried out the bombing. Some other sources include: Dan Ford, "How many died at Hiroshima?" (Dan Ford is an aviation and military history enthusiast); "Hiroshima and Nagasaki: The Physical, Medical, and Social Effects of the Atomic Bombings" (Committee on Damage by Atomic Bombs in Hiroshima and Nagasaki, 1981, London), cited in "A Photo-Essay on the Bombing of Hiroshima and Nagasaki" University of Illinois.

Additional Sources and Reading:

"The Atomic Bombings of Hiroshima and Nagasaki," Special Manhattan Engineer District Investigating Group, The United States Strategic Bombing Survey, The British Mission to Japan, and the Joint Atomic Bomb Investigating Group (Medical)

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