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143. Memorandum From the President’s Special Assistant for National Security Affairs (Cutler) to the Director of the Office of Civilian and Defense Mobilization (Hoegh)0

I talked with the President last night about Dr. McGrath’s excellent presentation to the Council yesterday morning on the hazards of radioactive [Page 562]fallout and on the relative effectiveness of types of protective measures.1

The President was interested in the difference, in terms of casualties, between an enemy attack using “dirty” nuclear weapons and an enemy attack using “clean” nuclear weapons. [3 lines of source text not declassified] there is confidence our scientific skill can within some five or more years solve this problem. Obviously a general war fought with “clean” weapons would not have the incalculable consequences to the world of a general war fought with “dirty” weapons, because of the greatly reduced radioactive fallout. Also the use of “clean” weapons in local conflicts (at least in many areas) would lessen the risk of such conflicts spreading into general war.

The presentation given to the Council yesterday included an example of massive nuclear attack on the U.S. with “dirty” weapons (Operation Alert 1957). This example showed the areas affected by radioactive fallout on the basis of two weather patterns on different days.

The President would be interested to see a comparison of estimated casualties resulting from the use of “dirty” nuclear weapons and estimated casualties resulting from the use of “clean” nuclear weapons, based on this attack pattern. While computations of casualties were not given at the presentation, I assume that they are available as to an attack using “dirty” weapons.

In fulfilling the President’s request, the following assumption might be made. The “clean” nuclear weapons to be used in the “clean nuclear weapons exercise” would be [less than 1 line of source text not declassified] “clean” nuclear weapons in all ranges. While at present to “clean” a “dirty” weapon reduces its yield by some [less than 1 line of source text not declassified] it is expected that future testing will greatly minimize such reduction in yield. For the purposes of simplification, your “clean nuclear weapons exercise” could well use “clean” weapons having the same yield as the “dirty” weapons used in the “dirty nuclear weapons [Page 563]exercise”. Captain Morse, AEC, will be very useful in assisting in this enterprise because of his intimate knowledge.

While I do not know about these matters myself, I am told that the additional estimates desired by the President would involve mostly machine computations based upon your existing estimates. Do you think it would be possible to have the two exercises and their results completed in time for the next Council meeting on March 27?2 This is not a requirement, but if it could be conveniently done it would be helpful.

Robert Cutler3
  1. Source: Eisenhower Library, White House Office Files, Project Clean Up, #5. Top Secret; Restricted Data. A copy was sent to John McCone, Chairman of the Atomic Energy Commission.
  2. On March 20, Paul McGrath of the Federal Civil Defense Administration briefed the National Security Council with a factual presentation on radioactive fallout and the types of protective measures against it as background to discussion of Agenda Item 1, “Measures To Carry Out the Concept of Shelter.” (Memorandum of discussion at the 359th NSC meeting, March 20; Eisenhower Library, Whitman File, NSC Records) See the Supplement, the compilation on National Security.

    On March 21, Cutler sent President Eisenhower a memorandum relating to their discussion on March 20. It reads in part:

    “In our talk last night relative to the importance to the United States of developing ‘clean’ nuclear weapons, I omitted in my advocacy one very important reason:

    “The ability to set off ‘clean’ nuclear detonations without contaminating nuclear radioactive fallout would have tremendous significance in the peaceful uses of atomic energy.” (Eisenhower Library, Whitman File, Administrative Series, Cutler, General Robert L., 1958 (3))

  3. On March 27, the NSC again discussed as Agenda Item 1, “Measures To Carry Out the Concept of Shelter.” Hoegh informed the Council that in the simulated surprise attack study upon the United States carried out in 1957, estimated U.S. casualties (dead and injured) would have been reduced from 51.3 million to 30.4 million people if only “clean” weapons had been used. (Memorandum of discussion at the 360th NSC meeting, March 27; ibid., Whitman File, NSC Records) See the Supplement, the compilation on National Security.
  4. Printed from a copy that indicates Cutler signed the original.