The best newspapers try to establish a firewall between the reporting staff and the editorial folk. Over the years, no paper has excelled at maintaining this barrier better than the Wall Street Journal. The reporters were first rate. The editorial page was called, either by Salon or Slate, I forget which, "a viper's nest of right-wing vitriol." When right-winger Rupert Murdoch acquired the WSJ, many people fretted that the separation of reporters and editors...