The WaPo's Outlook section had a really great article yesterday about why unions matter to the entire middle class. Professors Jacob Hacker and Paul Pierson detail the role that unions have played in American history, a role that has diminished in recent years. As the percen tage of workers in unions has declined, income inequality has exploded. That is not good for America. In the long run, it is not even good for the very rich. Gross income inequality invites the kind of class warfare Americans have always shunned. If there really is a moderate center of the electorate, they should be paying close attention to the attacks on labor in Wisconsin and Ohio - and they should shudder.