Bomb parents wonder what they did wrong

New technologies are creating new ethical dilemmas. Joseph Rotblat asks if an old one, the atomic bomb, still has lessons for the 21st century.

Should scientists be concerned about the social and moral issues arising from their work? Or should they be absolved from any responsibility on the grounds that all knowledge is good?

Such questions have been asked, mainly by philosophers, since the days of Francis Bacon and Rene Descartes. The questions became of general relevance during the 20th century, when science began to play a greater role in human affairs. And they are becoming more crucial at the threshold of the new millennium, with new technologies increasingly impinging on our lives.

Research into genetically modified food, for example, provokes controversy on social and economic grounds. Other aspects of genetic engineering, such as human cloning, are raising fundamental moral and ethical questions. On top of this, there is the threat of new weapons of mass destruction arising as a byproduct of scientific research. Similarly, developments in the fast-growing information technologies, such as nanotechnology, quantum computation and robotics, may result in intolerable strains and threats to society arising from an unequal distribution of benefits, or from an increasing vulnerability to terrorist activities.

It is, of course, the science behind the technology that creates the problems. The distinction between pure science and its application is becoming blurred. And it is science and scientists that are acquiring a bad public image, boding ill for the future, should such a state of affairs continue.

When tackling new issues, it is important to learn from experience. The most pertinent experience we have is in the application of nuclear physics to the production of nuclear weapons. This is why, after 55 years, there is still a need for books on the history of the atom bomb and the attitude of the scientists who built it. The two books reviewed here belong to this category.

Both books deal with the same main topic: the moral responsibility of scientists who worked on the Manhattan Project. But in other respects they could hardly be more different. One is a comprehensive, dispassionate study of the lives of two top scientists, written by a physics professor turned professional historian of science. The other is a cri de coeur of a woman about the guilt felt by her dying father for his part in the project.

The central figure in both books is the German-born American theoretical physicist, Hans Bethe. A Nobel laureate, Bethe is the most respected man in physics today, a legend in his own lifetime. He is the most senior of the survivors of the Manhattan Project and, at 94, probably the oldest.

Bethe is the direct inspiration for Silvan S. Schweber's book. Commissioned to write Bethe's biography, Schweber amassed a huge amount of material on Bethe, but after seven years of work on the complete biography, he came to the conclusion that this "would become three fat volumes that not many people would read". So he decided to break it up into several studies of parallel lives, each comparing and contrasting Bethe's life with that of another scientist.

In the Shadow of the Bomb is a study of the parallel lives of Bethe and J. Robert Oppenheimer. Both were intimately involved in the making of the atom bomb during the war and in the later decision to develop the hydrogen bomb, and the book treats in depth the ensuing moral issues. Although Bethe is the chief persona, Schweber's treatment of both is thorough and fair; it is on the basis of facts that Bethe comes off better in the comparison, as a man of integrity.

The image presented of Oppenheimer is very much the same as that I built up from my own observations: a brilliant scientist, an erudite scholar, a charismatic personality, but an errant, weak and unreliable character. Initially my hero, I came to the conclusion that Oppenheimer was a hero with feet of clay. I was particularly indignant about his despicable denunciation of a colleague, Bernard Peters, (an episode described in the book) which added to the general impression of Oppenheimer as a tragic figure, tormented by internal contradictions.

No such torments are apparent in Bethe's life, as described by Schweber. He alludes, but without elaboration, to some painful events and crises at home, but Bethe emerges as having a well-organised life, governed by a powerful intellect, pragmatism, and attention to detail; an ideal blend of brilliance and sitzfleisch (perseverance and endurance).

Pragmatism guided Bethe's views and actions during the making of the atom bomb, and his later service as a consultant at Los Alamos, as well as his participation in the movements of scientists against the use of nuclear weapons. He approved of the dropping of the atom bombs on Hiroshima and Nagasaki as the only rational option, but opposed on moral grounds the development of the hydrogen bomb. Later, however, he agreed to work on it using the argument that the H-bomb was needed because the Russians were going to have it.

Describing himself as a "tough dove", Bethe expounded the same views in the interviews he gave to Mary Palevsky, recorded in Atomic Fragments . During the second world war, her father, Harry Palevsky (as well as her mother) worked on the Manhattan Project in Los Alamos. He was horrified by the use of the bombs on Japan and retained a sense of contrition for his part in it. Anxious to prevent any further use of nuclear weapons, he participated in the Pugwash movement. Mary became acutely aware of his anguish after listening to the tapes he recorded before his death, at the time of the bitter public debate about the way the 50th anniversary of Hiroshima should be commemorated. She was deeply affected, and determined to learn more about the decision to use the bomb by seeking the views of senior members of the Manhattan Project.

By the late 1990s only a few of these scientists were still alive and Mary went to great lengths to interview them. The conversations with seven of them are the subjects of the seven chapters of her book, with the appropriate subtitle "A daughter's questions".

I was one of the interviewees; the remaining five were Edward Teller, Philip Morrison, Robert Wilson (who has since died), Herbert York and David Hawkins (a philosopher, who came to Los Alamos as an administrative assistant to Oppenheimer and wrote the first history of the project). Although the selection was determined mainly by virtue of longevity, between them the seven represent the full spectrum of opinion on the bomb, ranging from total support for the deterrence policy of consecutive US administrations (including the need for the "Star Wars" umbrella), to absolute opposition to the retention of any nuclear weapons. But it was Bethe who interested Palevsky most and to whom she turned time and time again with more questions about his justification of the first use of the bomb, in contrast with her father's views. At the end, her questions remained unanswered.

Both books quote - surprisingly with hardly a comment - the statement issued by Bethe in 1995, on the occasion of the 50th anniversary of Hiroshima, in which he called on scientists to cease and desist from work on nuclear, chemical and biological weapons. To me the statement was of great significance, and I quoted it in full in my Nobel lecture. This was the first time that a scientist of Bethe's stature had called for a boycott on work on the development of even potential weapons of mass destruction. If heeded, it would have brought to an end ongoing research projects, such as the huge Stewardship Project in the US, some aspects of which, however, Bethe seems to support. Do we see the great man, the paragon of stability and rationality, finally succumbing to doubts and internal contradictions?

I commend both books. Atomic Fragments is the more readable; I found it deeply moving and its style will appeal to a wide audience. In the Shadow of the Bomb is a learned discourse, delving into the philosophy of morality, as well as analysing important aspects of education and science, but it requires a high degree of concentration.

When reviewing books I usually refrain from pointing out mistakes or criticising the structure, but I have to make an exception in the case of Schweber's book. Written by a professional historian, and thoroughly researched, it is surprising to find mistakes in quoting dates. For example, when deploring the fact that early in 1939 none of the great men in physics tried to declare a moratorium on the construction of nuclear weapons, his list includes Ernest Rutherford, who had died in 1937.

More serious is the misdating of events relating to the British effort on the atom bomb; this occurs several times, creating the impression of an attempt to downgrade its significance. Thus he states that Germany started the bomb project two years earlier than Britain and the US, while, in fact, work in England had already started in 1939. By 1941 research in the UK had established the scientific feasibility of the bomb, while in the US no effort on the bomb was made in earnest until it was stimulated by Marcus Oliphant.

My other complaint is about a feature - now becoming common in publications of this type - of putting much of the material in the form of notes at the end of the text. Schweber has probably achieved a record in this respect, with 635 notes on 192 pages of narrative (quite apart from 375 references).

This means that, on average, I had to turn to the end of the text three or four times for each page read - highly distracting and frustrating. Some of the notes are long and many are of great interest and more directly related to the narrative than matter included in the text. Indeed, it is difficult to discern the criteria used in the allocation of the material. In my opinion, any material relevant to the narrative should be included in the text, and the author should take the trouble to weave it into the story even if this means more work to preserve continuity. Books are written to be read, and authors should keep this in mind.

Sir Joseph Rotblat, Nobel laureate, is emeritus professor of physics, University of London, and emeritus president, Pugwash.