When World War II ended with the use of atomic weapons which had been developed in secret by the Manhattan Project, Hecht was concerned that the American public was uninformed about the development of this new source of energy. He wrote a book Explaining the Atom (1947), to educate the public. He wrote,
:So long as one supposes this business is mysterious and secret, one cannot have a just evaluation of our possessions and security. Only by understanding the basis and development of atomic energy can one judge the legislation and foreign policy that concern it.
In a review in the New York Times (4/27/1947), Stephen Wheeler wrote that it was "by all odds the best book on atomic energy so far to be published for the ordinary reader." Similarly, James J. Jelinek wrote that it was an "invaluable contribution to the layman." He credits Hecht with "conveying to the layman the intellectual drama" of the development. Jelinek asserts that the book is "profoundly provocative in its political and sociological implications."
After Hecht died, a second edition was issued in 1959 by Eugene Rabinowitch. Both editions were recommended by George Gamow.