Veteran musical popularizer David Ewen writes the score on the men who made musical theatre in America. A brief reprise on the ancestors from the first native musical stage production, the minstrel show, through The Black Crook and A Trip to Chinatown; then on to Messrs, Herbert, Friml and Romberg, who ""ruled American operetta when it was in its full glory."" There follow George M. Cohan, Father of Musical Comedy; Jerome Kern (Shew Beat was his finest hour), lrving Berlin, whose ""White Christmas"" a la Bing has sold twenty-five million copies; Cole Porter, who rose from a wheelchair to write Kiss Me Kate; Richard Rodgers, father, with Hammerstein, of the musical play (Oklahomal, Carousel); Kurt Weill, Frederick Loewe, Frank Loesser and Jerry Bock. Lastly, Lenny. . . . Pro job.