A group of distinguished Manhattan Project scientists based at the University of Chicago’s Metallurgical Laboratory were among the first to consider whether or how to use atomic bombs in World War II.

The Met Lab’s primary challenge was to establish proof of concept for a nuclear chain reaction and plutonium production. Then the action moved elsewhere. Met Lab scientists had more time and distance from their colleagues at Los Alamos, Hanford and Oak Ridge to have second thoughts about their collective efforts.

The man who chaired their secret deliberations in Chicago was James Franck, a Nobel Prize-winning physicist who served as Director of the Chemistry Division at the Met Lab. Like many other scientists working on the Bomb, Franck was a refugee from war-torn Europe. Other participants in this drafting effort included Eugene Rabinowitch, Glenn T. Seaborg, and especially Leo Szilard.

Completed two months before Hiroshima, the Franck Report urged the Truman administration to carry out a demonstration shot of the atomic bomb rather than to use it without advance warning against a Japanese city.

Here are some of the key passages:

“If no efficient international agreement is achieved, the race of nuclear armaments will be on in earnest not later than the morning after our first demonstration of the existence of nuclear weapons. After this, it might take other nations three or four years to overcome our present head start, and 8 or 10 years to draw even with us if we continue to do intensive work in this field.”

“Even though Russia, in particular, has an immense space over which its vital industries could be dispersed and a government which can order this dispersion, the day it is convinced that such a measure is necessary – there is no doubt that Russia, too, will shudder at the possibility of a sudden disintegration of Moscow and Leningrad, almost miraculously preserved in the present war, and of its new industrial sites in the Urals and Siberia. Therefore, only lack of mutual trust, and not lack of desire for agreement, can stand in the path of an efficient agreement for the prevention of nuclear warfare. From this point of view, the way in which nuclear weapons, now secretly developed in this country, will first be revealed to the world appears of great, perhaps fateful importance.”

“One possible way – which may particularly appeal to those who consider the nuclear bombs primarily as a secret weapon developed to help win the present war – is to use it without warning on an appropriately selected object in Japan… If we consider international agreement on total prevention of nuclear warfare as the paramount objective, and believe that it can be achieved, this kind of introduction of atomic weapons to the world may easily destroy all our chances of success. Russia, and even allied countries which bear less mistrust of our ways and intentions, as well as neutral countries, will be deeply shocked. It will be very difficult to persuade the world that a nation which was capable of secretly preparing and suddenly releasing a weapon, as indiscriminate as the rocket bomb and a thousand times more destructive, is to be trusted in its proclaimed desire of having such weapons abolished by international agreement.”

“Thus, from the ‘optimistic’ point of view – looking forward to an international agreement on prevention of nuclear warfare – the military advantages and the saving of American lives, achieved by the sudden use of atomic bombs against Japan, may be outweighed by the ensuing loss of confidence and wave of horror and repulsion, sweeping over the rest of the world, and perhaps dividing even the public opinion at home. From this point of view a demonstration of the new weapon may best be made before the eyes of representatives of all United Nations, on the desert or a barren island. The best possible atmosphere for the achievement of an international agreement could be achieved if America would be able to say to the world, ‘You see what weapon we had but did not use. We are ready to renounce its use in the future and to join other nations in working out adequate supervision of the use of this nuclear weapon.’”

“It must be stressed that if one takes a pessimistic point of view and discounts the possibilities of an effective international control of nuclear weapons, then the advisability of an early use of nuclear bombs against Japan becomes even more doubtful – quite independently of any humanitarian considerations. If no international agreement is concluded immediately after the first demonstration, this will mean a flying start of an unlimited armaments race. If this race is inevitable, we have all reason to delay its beginning as long as possible in order to increase our headstart still further.”

In late May and June, 1945, Secretary of War Henry L. Stimson and his “Interim Committee” were also considering whether and how to use the Bomb. For reasons discussed in an earlier post (“The Least Abhorrent Choice,” August 24, 2010), Stimson and his advisers, including J. Robert Oppenheimer, found the Franck Report’s recommendations to be unpersuasive.

Update | 12 June 2011 11:19 am Another wonderful post by Michael.  As is noted in the comments, there are a couple of versions (1, 2) of the Franck Report floating around because it was originally stamped secret.  I remember some slight differences, but don’t have time right now to spot them again.  Someone (Wellerstein!) should make a high-resolution image from the National Archives so that we have a definitive copy.