Book excerpt: People have worried for many years about the concentration of private power over the media, as evidenced by controversy over Federal Communication Commission rulings on broadcast ownership limits. The fear, it seems, is of a media mogul with a political agenda: a new William Randolph Hearst who could help start wars or run for political office using the power of the media. In the light of these concerns about freedom of speech, Eli Noam provides a comprehensive survey of media concentration in America, covering everything from the early media empire of Benjamin Franklin to the modern-day cellular phone industry.