“Documentaries are, in fact, defined by what’s left out,” writes filmmaker David Grubin, describing the editorial choices he made in producing The Jewish Americans. “They are not meant to be encyclopedic.” He tells a viewer disappointed by the show’s limited treatment of Jewish Americans in the western United States that the strength of documentaries is in combining the “emotional power of music and imagery,” which “can make you feel as if you are experiencing history rather than learning it.” Grubin responded to questions from viewers of his PBS series in a two-part New York Times online Q&A.