Herb York, who died on 19 May at the age of 87, was present at the creation of the US postwar defence research and development establishment and, from a very early date, was one of its scientific leaders. He also quickly recognized the limitations of technology in providing security, and became a leader in arms control and in educating younger people on the complexities of our nuclear age. York was unflappable, always accessible and always open to a good argument. His initiatives in defence, arms control and education continue to shape key institutions in the United States.


During the Second World War, York worked on the Manhattan Project to develop nuclear weapons. After the atom bomb was dropped over Hiroshima on 6 August 1945, he concluded that war had finally become too terrible to fight, “not know[ing]”, as he later wrote, “that the same thing had been said many times before”. A sense of responsibility for the consequences of the atom bomb never left him.

In 1952, he was picked by Ernest Lawrence from the obscurity of an assistant professorship in physics at the University of California (UC), Berkeley, to lead what became the Lawrence Livermore National Laboratory. During York's six years there (Lawrence suggested he call himself director after the first year and a half), the laboratory grew from about 100 people to 3,000, and among other tasks was entrusted with the development of the warhead for the first submarine-launched missile, Polaris. The laboratory pioneered several techniques, among them the use of the largest computers then available (which were less powerful than today's laptops) to model complex events such as nuclear explosions. As with most good labs, constant review and questioning of assumptions, goals and methods were the norm. But York added a good-humoured, positive yet realistic attitude, in which setbacks were cause for learning rather than finger-pointing criticism.

In 1957, York was asked by the first presidential science adviser, James Killian, to join the President's Science Advisory Committee, which President Dwight Eisenhower had just founded in response to the Soviet launch of the Sputnik satellite. Several of the main lines of today's defence establishment were created then, particularly as regards nuclear forces and research and development. On the committee, York was a major influence in starting what is now called the Defense Advanced Research Projects Agency, a (comparatively) freewheeling research and development establishment within the Pentagon, which was supposed to — and to this day does — introduce new technological ideas into the system. He was promptly named as its first chief scientist and then became the first director of Defense Research and Engineering, a post from which he both supervised and moderated the burgeoning US missile forces.

York was also instrumental in transferring the US Army's space facility at Huntsville, Alabama (where the German rocket expert Wernher von Braun and his colleagues had landed at the end of the Second World War), and the Jet Propulsion Laboratory at the California Institute of Technology in Pasadena, to NASA. He thereby helped to place space exploration in the United States firmly in civilian hands.

It was from those years that York came to have a sober view of what the military–industrial–congressional complex would do without (and sometimes despite) politically powerful and technically well-informed supervision. In this he was very much in tune with Eisenhower. Both were ahead of the political establishment of the time and had mixed success.

After recovering from a serious heart attack in 1960, York became the founding chancellor of UC San Diego, a campus dedicated to excellence in science. He served four years in that post and remained at the university as professor of physics for the rest of his life. He served a second term as interim chancellor from 1970 to 1972.

Throughout that period, York continued to work on the issues raised by the nuclear age, particularly arms control and non-proliferation. Joseph Nye, then deputy to the undersecretary of state for security assistance, science and technology, and chair of the National Security Council Group on Nonproliferation of Nuclear Weapons, remembers him “as a mature, insightful and calming presence as an adviser as we developed [President] Carter's non- proliferation policy”. Carter also appointed York as the ambassador leading the US delegation in negotiating a Comprehensive Test Ban Treaty in 1979.

In the early1980s, York was instrumental in getting Jerry Brown, governor of California, and UC president David Saxon to set up the Institute on Global Conflict and Cooperation (IGCC), which is dedicated to research and teaching in the area of preventing war. The institute's creation was the realization of York's goal that the Second World War, and especially Hiroshima, had inspired forty years before. It spans several UC campuses as well as the nuclear-weapons laboratories, which were then managed by the university. York served as the first director and continued to contribute to it until his death.

Several of his initiatives at the IGCC continue, such as the summer nuclear-weapons policy training programmes and the Track 2 dialogues, which are informal conversations among officials from different countries on particular issues. He also made a more personal contribution: he linked today's students and young researchers to the time when nuclear weapons were first introduced, putting a human face on how the new dilemmas were resolved or not, and why policy responses took the shape that they did. York combined realistic assessments of the dangers with advocacy for steps to alleviate them, all of this serious work being enlightened by his sunny, open disposition.

Herb York won most of the honours available in his various fields, including the 1994 Leo Szilard Lectureship Award and the 2000 Enrico Fermi Award and published six books about his experiences and views. He exemplified how scientists can best serve the common cause in a dangerous and controversial area, despite the many puzzles and contradictions that such service implies. He did it with a sense of balance, good humour and decency under pressure that continues to encourage the rest of us.