George Bogdan Kistiakowsky (November 18, 1900 – December 7, 1982) was a physical chemist who taught and conducted research in thermochemistry and reactions at Harvard University, was the leader of the chemical explosives team of the Manhattan Project and later served as President Eisenhower's Science Advisor. While he made major contributions to science policy, arms control, and chemistry, he also saw himself as a teacher:
It is far more important to be interesting than to be thorough or erudite, for if we have the interest of a beginning student, we can easily lead him to read more on his own or to take further courses that will be rigorous and complete.
In 1925, he earned his Ph.D. in physical chemistry from the University of Berlin. In 1926, he came to the United States and taught at Princeton University for two years, and then joined the faculty of Harvard University, an affiliation that continued through his later career.
At Harvard, his research interests were in thermodynamics, spectroscopy, and chemical kinetics. He became increasingly involved with consulting for the government and industry. After the start of WWII, he headed the National Defense Research Committee's Explosives Division.
He joined the Manhattan Project in 1944, replacing Seth Neddermeyer as head of the "X" division responsible for the explosive components of fission weapons. Under his leadership the complex explosive lenses needed to compress the plutonium sphere uniformly to achieve critical mass were developed.
White House Service
During the Eisenhower administration he served on the President's Science Advisory committee for several years, becoming the Science Advisor to the President in 1959. After the Kennedy Inauguration, he was still consulted. He directed the Office of Science and Technology Policy from 1959 to 1961, and was succeeded by Jerome B. Wiesner.
In 1958, Kistiakowsky suggested to President Eisenhower that inspection of foreign military facilities was not sufficient to control their nuclear weapons. He cited the difficulty in monitoring missile submarines, and proposed that the arms control strategy focus on disarmament rather than inspections . Subsequently in January 1960, as part of arms control planning and negotiation, he suggested the "threshold concept". Under this proposal, all nuclear tests above the level of seismic detection technology would be forbidden. After that agreement, the US and the USSR would work jointly to improve detection technology, revising the permissible test yield downward as techniques improved. This example of the "national means of technical verification", a euphemism for sensitive intelligence collection used in arms control, would provide safeguards, without raising the on-site inspection requirement to a level unacceptable to the Soviets.
The US introduced the threshold concept to the Soviets at the Geneva arms control conference in January 1960, and the Soviets, in March, responded favorably, suggesting a threshold of a given seismic magnitude. Talks broke down as a result of the U-2 incident in May.
At the same time as the early nuclear arms control work, the Chairman of the Joint Chiefs of Staff, General Nathan Twining, USAF, sent a memorandum , in August 1959, to the United States Secretary of Defense, Neil McElroy, which suggested that the Strategic Air Command formally be assigned the responsibility to prepare the national nuclear target list, and a single plan for nuclear operations. Up until that point, the Army, Navy and Air Force had each done their own target planning which led to individual targets being over-selected for destruction by two or more services. The separate service plans were not mutually supporting, as, for example, by the Navy destroying an air defense facility that an Air Force bomber could have destroyed on route to a deeped target. While Twining had sent the memo to McElroy, the members of the Joint Chiefs of Staff disagreed on the policy during early 1960.  . Thomas Gates, who succeeded McElroy, asked President Dwight D. Eisenhower to decide the policy. 
Eisenhower said he would not "leave his successor with the monstrosity" of the uncoordinated forces and their existing plans. In early November 1960, he sent Kistiakowsky to the Strategic Air Command (SAC) Headquarters in Omaha to evaluate the SAC war plans. Initially, Kistiakowsky was not given access, and Eisenhower sent him back to Omaha with a much stronger set of orders, giving SAC officers the choice to cooperate with Kistiakowsky or resign. 
Kistiakowsky's report, presented on November 29, described uncoordinated plans with huge numbers of targets, many of which would be attacked by multiple forces, resulting in overkill. Eisenhower was shocked by the plans, and focused not just on the creation of the Single Integrated Operational Plan (SIOP), but on the entire process of picking targets, generating requirements and planning for nuclear war operations.
In the Kennedy Administration, the Assistant to the President for National Security Affairs, McGeorge Bundy, wrote to John F. Kennedy, on January 31, 1961, that there needed to be a "review of basic military policy. What is our view of the kind of strategic force we need, the kinds of limited-war forces, the kind of defense for the continental U.S., and the strategy of NATO?"  Bundy proposed that Kistiakowsky conduct scientific evaluation of Air Force nuclear plans, which Bundy suggested that Air Force planning is based on very doubtful technical judgments on the damage that will be done by given weapons exploded on given targets. He proposed Kistiakowsky do this study, "and the result might show that we need much less expensive plans than we now have."
After the Manhattan Project, and then after his White House service, Kistiakowsky was a professor of physical chemistry at Harvard for the rest of his career. From 1962 to 1965, he chaired the National Academy of Sciences Committee on Science, Energy, and Public Policy (COSEPUP) .
In later years he was active in an antiwar organization, the Council for a Livable World . According to the Council biography of Kistiakowsky, "Kistiakowsky became increasingly doubtful about the possibility of changing politics from within the administrative channels in Washington. In 1968, Kistiakowsky severed his connections with the Pentagon to protest U.S. involvement in Vietnam. After retiring from Harvard as professor emeritus in 1972, Kistiakowsky became even more involved in political activism in the areas of de-escalating the arms race and banning nuclear weapons. In 1977, he assumed the chairmanship of the Council for Livable World, campaigning to de-escalate the arms race and reorient the domestic political agenda."
- Office of History & Heritage Resources, Implosion becomes a Necessity, The Manhattan Project: An Interactive History, U.S. Department of Energy
- , Space Policy Project (summary of Foreign Relations of the US, text not online), Foreign Relations of the United States 1958-1960, vol. National Security Policy; Arms Control and Disarmament, Volume III, Washington, DC: US Department of State (summary by Federation of American Scientists), 1961, FRUS58
- Nathan Twining (20 August 1959). Document 2: J.C.S. 2056/131, Notes by the Secretaries to the Joint Chiefs of Staff, enclosing memorandum from JCS Chairman Nathan Twining to Secretary of Defense, "Target Coordination and Associated Problems,". The Creation of SIOP-62: More Evidence on the Origins of Overkill National Security Archive Electronic Briefing Book No. 130. George Washington University National Security Archive. Retrieved on 2007-09-22.
- Twining, Nathan F. (5 October 1959). Document 3A: JCS 2056/143, Note by the Secretaries to the Joint Chiefs of Staff, 5 October 1959, enclosing Memorandum for the Joint Chiefs of Staff, "Target Coordination and Associated Problems,". The Creation of SIOP-62: More Evidence on the Origins of Overkill National Security Archive Electronic Briefing Book No. 130. George Washington University National Security Archive. Retrieved on 2007-09-22.
- Burke, Arleigh (30 September 1959). Document 3B: attached memorandum from Chief of Naval Operations. The Creation of SIOP-62: More Evidence on the Origins of Overkill National Security Archive Electronic Briefing Book No. 130. George Washington University National Security Archive. Retrieved on 2007-09-22.
- McKinzie, Matthew G. & Thomas B. Cochran (2001), The U.S. Nuclear War Plan: A Time for Change, vol. Chapter Two: The Single Integrated Operational Plan and U.S. Nuclear Forces, National Resources Defense Council
- Bundy, McGeorge (1961), Memorandum for the President: Policies previously approved in NSC which need review, Foreign Relations of the United States, 1961-1963, vol. Volume VIII, National Security Policy, Washington, DC: U.S. Department of State, at 9
- Origins of COSEPUP. National Academy of Sciences.
- Council for a Livable World. Legacy.