NOWHERE HAS THE swords into plowshares analogy been invoked more often than in the relationship between the military and civilian uses of nuclear energy. But in recent years we have become increasingly aware of a defect in the analogy: nuclear swords and nuclear plowshares are not always readily distinguishable, nor are the technologies and materials associated with their production. In The Greatest Power on Earth, Ronald W. Clark unfolds the early histories of nuclear weapons and civilian nuclear power, and demonstrates that the histories too are inseparable.

Beginning at Einstein's revelation in 1905 of E=mc2 ("pulled from the intellectual stratosphere"), Clark guides us along the path of scientific progress to the discovery of fission; then along the technological trail past the milestones of the first nuclear reactor, the production of uranium and plutonium suitable in both quality and quantity for weapons, and the successful testing of an atomic bomb; and then down the military road to the dropping of two bombs on Japan and the beginnings of a full blown international nuclear arms race. Along the way we encounter alternate routes leading to the development of nuclear power reactors for the propulsion of submarines and the production of electricity. The journey is described in terms understandable to the non-technical reader.

Fortunately, Clark's abilities are not limited to those of a popular interpreter of science and technology (though his skill at such translation is as evident and valuable here as in his 1971 biography, Einstein: The Life and the Times). That aspect of nuclear history has been written of before and by many, though rarely as well. Clark's special gift, demonstrated in this book, is his ability to combine in a single, uninterrupted, and engrossing narrative both the technical and human dimensions of this fascinating story. Here we read how the free exchange of information among scientists searching for soloutions to nuclear riddles was changed into a deadly contest shrouded by secrecy; how the oppressive anti-Semitic policies of Hitler's Germany contributed a flow of fertile scientific minds to the nuclear programs of the wartime Allies; how cooperation among the allied nations (other than the Soviet Union) was transformed into intra-alliance competition by their reluctance to share any potential economic benefits of civilian nuclear power; how the perceptions in each nation of other nations' progress toward the bomb compared with realty; how the people involved in the wartime activities perceived the moral implications of their efforts; and how the first nuclear explosion led inexorably to the inclusion of nuclear weapons in military aresenals.

Clark draws heavily on original sources, and makes effective use of direct quotations from them. An example is his treatment of the reception given to the publication in 1914 of H. G. Wells' The World Set Free , which first forecast the release of nuclear energy and the effects of nuclear war. A "'porridge composed of Mr. Wells's vivid imagination, his discontents and his Utopian aspirations', as The Times Literary Supplement called it" writes Clark. Lest the reader err in thinking that this evaluation was unique, Clark provides another review: "'The nightmare will not come true,' Blackwood's Magazine comfortably commented, 'and we shall go on living a life of reasonable happiness, committing follies and paying for them, and doing our duty in the old fashion, indifferent whether it is a horse we ride behind or a steam-engine that wafts us on our way . . . even the atomic energy imagined by Mr. Wells would be powerless always against the unbroken traditions of the human race.'" Within a few years of the appearance of Wells' book, British physicists Francis Aston, Oliver Lodge and Ernest Rutherford provided guarded credibility to the notion of unleashing the energy bound in the atomic nucleus. But the vision was not then shared uniformly. Einstein, when approached in 1921 "by a young man who had ideas for a weapon based on the mass-energy equation," dismissed the idea as "foolishness." It was not until 1938, when the results of experiments conducted by Otto Hahn and Fritz Strassman in Berlin were explained by Lise Meitner and Otto Frisch--two Jewish refugees from Hitler--that the scientific world accepted nuclear fission as fact, and with that acceptance began racing toward nuclear kilotons and nuclear kilowatts.

Clark contributes much to our understanding of the wartime nuclear efforts of the United States, England, France and Canada, with special attention to the political dimensions of the Anglo-American nuclear relationship. He offers also some interesting tidbits on the German and Russian programs. "What," he asks, "had been happening in the Third Reich, Hitler's Germany where Hahn and Strassmann had kicked the pebble to start the nuclear avalanche? The answer is that more had been going on than is generally realized even today." Maintaining that "many if not most German phyicists entered the race for reasons very similar to those of scientists elsewhere: in the hope that their country would be able to command a unique weapon," Clark argues that the central reason for the German failure was their belief that the bomb would have to be similar in design to a nuclear reactor in which low-energy neutons cause the fissions. They were wrong. The Russians did not make the same mistake. Their theoretical work pointed in the right direction, but the wartime drain on Russian resources was simply too great to permit a nuclear effort of the scale required to keep pace with the United States. Time was to tell that they were only four years behind.

In the final chapters, Clark reflects all-too-briefly on the problems and prospects of nuclear arms control and the perils and promise of the worldwide spread of nuclear power facilities. He closes on a somber note:

"It would be tragic if a limited nuclear exchange, halted after each side had experienced the agony of one city put to the bomb, were necessary to bring men to their senses and to realize, at last, that there are no victors in nuclear war. It would be equally tragic if the melt-down of a power-producing reactor and the creation of a trial of disaster across Britain, the state of New York, or Western Europe, were needed to bring about a radical reassessment of how nuclear power should fit ito the world's energy problem. But failing such events we may go on to fumble the last catch of all."

This book offers no formula for survival. It is left to the reader to heed the author's warning and to act accordingly.