IF SPEECH BY a single individual in a single forum has the power to annoy, offend, incite, mislead, and endanger other members of society, so much more so does speech that is spread by newspapers, magazines, television, radio, books, the Internet, and record companies. At the same time, such speech also has a great capacity to exert a positive force, whether by educating and connecting people, disseminating beauty and art, or spreading ideas. The protection granted to these outlets, originally referred to as freedom of the press, today might more accurately be called media freedoms.

In recent years, the media have come under fire for producing films, music, magazines, books, and other material that many find deeply disturbing, often depicting bloody violence and graphic sex. The U.S. Congress, as well as many state legislatures, has responded to public pressures by considering, and in...