THE LEFTISTS ARE WHINING again. In the ‘80s, they sniveled, "Why is talk radio right-wing?" In the ‘90s, they wept, "Why do conservatives rule the Internet?" Now a new version of the same old complaint has arisen: "Why are all the blog sites conservative?" The answer to all three questions is the same. Talk radio, webzines, list servers, message boards and now blog sites have one thing in common. They are interactive. They let people talk back. Consequently, it is physically impossible for new media to do what old media did – that is, to shove unpopular ideas down peoples’...