This week I thought I'd say something about America's famous ''liberal media bias'': Bring it on, baby! That's the short version. The long version is that, as some readers may recall, after the midterm elections a year ago, I decided that ''liberal media bias'' was far more harmful to liberals than conservatives. In fact, if I were a Democrat, I'd be getting a little miffed at the recurring pattern: Throughout the election campaign, my newspaper produces a poll showing my guy way ahead; finds ''typical voters'' (choreographers of environmentalist dance companies, etc.) anxious to blame President Bush for the worst...