26 January 1962
Dear Mr. President:
I urge that you not order the resumption of atmospheric tests of nuclear weapons by the United States.
So far the United States has carried out about twice as many test explosions of nuclear weapons as the Soviet Union. The
megatonnage of the bombs tested by the Soviet Union is about 60 percent greater than that of the bombs tested by the United
States, but it is the number of tests, rather than the total megatonnage, that determines the amount of information obtained.
There is no doubt that the United States still has a great lead over the Soviet Union in nuclear weapons technology.
It is not necessary for the protection of the United States and the American people for our government to resume nuclear testing
in the atmosphere.
There is general agreement among biological scientists about the biological effects of radioactive fallout. No one can deny
that the fission products produced by these tests in the atmosphere cause genetic mutations that will lead to the birth of
grossly defective children. The number of defective children produced by these fission products and by high-energy radiation
in general cannot be accurately estimated. The estimates made by the most reliable American geneticists, agreeing also with
the estimates of the United Nations Committee on this subject, are in the neighborhood of 1,000 grossly defective children
per megaton of fission.
Moreover, the carbon 14 produced by the neutrons released in the explosion, even in the explosion of so-called "clean" bombs,
will, according to the most reliable estimates, produce a considerably larger number of defective children than the fission
products, provided that the human race continues to exist on earth during the lifetime of the carbon-14 nuclei.
In addition, many scientists, although not all, think that it is highly probable that radioactive fission products and carbon
14 damage human beings now living, as well as those of future generations, in such a way as to cause leukemia, bone cancer,
and other diseases.
I have no doubt that we could destroy the Soviet Union with the bombs that we now have, even after an initial attack, and
I believe that our danger would not be at all increased by our refraining from bomb testing for the foreseeable future. In
the meantime, our efforts toward achieving peace and disarmament would be made more effective by our moral position and by
our enhanced standing with the neutral nations if we were to refrain from carrying out any further tests of nuclear weapons.
I urge that further testing of nuclear weapons not be ordered, and that instead an increased effort be made to achieve a bomb-test
agreement, with international controls and inspection, and other agreements leading to the goal of general and complete disarmament
with control and inspection.