Arlen Specter has left the Republican Caucus and become a Democrat. Why? The ostensible reason was because Republicans were dominated by the far right. DHS Secretary Janet Napolitano issued a dire warning to watch out for members of the far right in combating the nonexistent threat of "domestic terrorism." Again, the far right is the bogeyman. Listen to Nancy Pelosi or Barney Frank or MSNBC reporters or the New York Times. What is the mythical danger? It is the "far right." Now, the far right of the liberals' imagination simply does not exist. Those accused of representing the mythical "far...