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Szilard Petition

Leo Szilard drafted the petition below to the President in the summer of 1945 attempting to avert the U.S.’s use of the atomic bomb against Japan. Although the petition was signed by seventy other scientists of the Met Lab in Chicago, it was never seen by the President or the Secretary of War before the first atomic bomb was dropped on Hiroshima.

Document Type:
Leo Szilard. Photo courtesy of Argonne National Laboratory


July 17, 1945

Discoveries of which the people of the United States are not aware may affect the welfare of this nation in the near future. The liberation of the atomic power which has been achieved places atomic bombs in the hands of the Army. It places in your hands, as Commander-in-Chief, the fateful decision whether or not to sanction the use of such bombs in the present phase of the war against Japan.

We, the undersigned scientists, have been working in the field of atomic power. Until recently we have had to fear that the United States might be attacked by atomic bombs during this war and that her only defense might lie in a counterattack by the same means. Today, with the defeat of Germany, this danger is averted and we feel impelled to say what follows:

The war has to be brought speedily to a successful conclusion and attacks by atomic bombs may very well be an effective method of warfare. We feel, however, that such attacks on Japan could not be justified, at least not until the terms which will be imposed after the war on Japan were made public in detail and Japan were given an opportunity to surrender.

If such public announcement gave assurance to the Japanese that they could look forward to a life devoted to peaceful pursuit in their homeland and if Japan still refused to surrender, our nation might then, in certain circumstances, find itself forced to resort to the use of atomic bombs. Such a step, however, ought not to be made at any time without seriously considering the moral responsibilities which are involved.

The development of atomic power will provide the nations with new means of destruction. The atomic bombs at our disposal represent only the first step in this direction, and there is almost no limit to the destructive power which will become available in the course of their future development. Thus a nation which sets the precedent of using these newly liberated forces of nature for purposes of destruction may have to bear the responsibility of opening the door to an era of devastation on an unimaginable scale.

If after the war a situation is allowed to develop in the world which permits rival powers to be in uncontrolled possession of these new means of destruction, the cities of the United States as well as the cities of other nations will be in continuous danger of sudden annihilation. All the resources of the United States, moral and material, may have to be mobilized to prevent the advent of such a world situation. Its prevention is at present the solemn responsibility of the United States—singled out by virtue of her lead in the field of atomic power.

The added material strength which this lead gives to the United States brings with it the obligation of restraint and if we were to violate this obligation our moral position would be weakened in the eyes of the world and in our own eyes. It would then be more difficult for us to live up to our responsibility of bringing the unloosened forces of destruction under control.

In view of the foregoing, we, the undersigned, respectfully petition: first, that you exercise your power as Commander-in-Chief, to rule that the United States shall not resort to the use of atomic bombs in this war unless the terms which will be imposed upon Japan have been made public in detail and Japan knowing these terms has refused to surrender; second, that in such an event the question whether or not to use atomic bombs be decided by you in the light of the consideration presented in this petition as well as all the other moral responsibilities which are involved. 

[Names and titles by Szilard biographer Gene Dannen]

  1. David S. Anthony, Associate Chemist
  2. Larned B. Asprey, Junior Chemist, S.E.D.
  3. Walter Bartky, Assistant Director
  4. Austin M. Brues, Director, Biology Division
  5. Mary Burke, Research Assistant
  6. Albert Cahn, Jr., Junior Physicist
  7. George R. Carlson, Research Assistant-Physics
  8. Kenneth Stewart Cole, Principal Bio-Physicist
  9. Ethaline Hartge Cortelyou, Junior Chemist
  10. John Crawford, Physicist
  11. Mary M. Dailey, Research Assistant
  12. Miriam Posner Finkel, Associate Biologist
  13. Frank G. Foote, Metallurgist
  14. Horace Owen France, Associate Biologist
  15. Mark S. Fred, Research Associate-Chemistry
  16. Sherman Fried, Chemist
  17. Francis Lee Friedman, Physicist
  18. Melvin S. Friedman, Associate Chemist
  19. Mildred C. Ginsberg, Computer
  20. Norman Goldstein, Junior Physicist
  21. Sheffield Gordon, Associate Chemist
  22. Walter J. Grundhauser, Research Assistant
  23. Charles W. Hagen, Research Assistant
  24. David B. Hall, Position Not Identified
  25. David L. Hill, Associate Physicist, Argonne
  26. John Perry Howe, Jr., Associate Division Director, Chemistry
  27. Earl K. Hyde, Associate Chemist
  28. Jasper B. Jeffries, Junior Physicist, Junior Chemist
  29. William Karush, Associate Physicist
  30. Truman P. Kohman, Chemist-Research
  31. Herbert E. Kubitschek, Junior Physicist
  32. Alexander Langsdorf, Jr., Research Associate
  33. Ralph E. Lapp, Assistant To Division Director
  34. Lawrence B. Magnusson, Junior Chemist
  35. Robert Joseph Maurer, Physicist
  36. Norman Frederick Modine, Research Assistant
  37. George S. Monk, Physicist
  38. Robert James Moon, Physicist
  39. Marietta Catherine Moore, Technician
  40. Robert Sanderson Mulliken, Coordinator Of Information
  41. J. J. Nickson, [Medical Doctor, Biology Division]
  42. William Penrod Norris, Associate Biochemist
  43. Paul Radell O’Connor, Junior Chemist
  44. Leo Arthur Ohlinger, Senior Engineer
  45. Alfred Pfanstiehl, Junior Physicist
  46. Robert Leroy Platzman, Chemist
  47. C. Ladd Prosser, Biologist
  48. Robert Lamburn Purbrick, Junior Physicist
  49. Wilfred Rall, Research Assistant-Physics
  50. Margaret H. Rand, Research Assistant, Health Section
  51. William Rubinson, Chemist
  52. B. Roswell Russell, Position Not Identified
  53. George Alan Sacher, Associate Biologist
  54. Francis R. Shonka, Physicist
  55. Eric L. Simmons, Associate Biologist, Health Group
  56. John A. Simpson, Jr., Physicist
  57. Ellis P. Steinberg, Junior Chemist
  58. D. C. Stewart, S/Sgt S.E.D.
  59. George Svihla, Position Not Identified [Health Group]
  60. Marguerite N. Swift, Associate Physiologist, Health Group
  61. Leo Szilard, Chief Physicist
  62. Ralph E. Telford, Position Not Identified
  63. Joseph D. Teresi, Associate Chemist
  64. Albert Wattenberg, Physicist
  65. Katharine Way, Research Assistant
  66. Edgar Francis Westrum, Jr., Chemist
  67. Eugene Paul Wigner, Physicist
  68. Ernest J. Wilkins, Jr., Associate Physicist
  69. Hoylande Young, Senior Chemist
  70. William Houlder Zachariasen, Consultant


More Historical Resources:

The Szilard Petition. The Szilard Petition. Photo courtesy of the Harry S Truman Library.