A Missed Point About Unions

by Smitty
Gary Gross over at Let Freedom Ring points to a NYT article about unions being less than united about health care reform:

Two labor unions have pulled out of a broad coalition seeking agreement on major changes in the health care system.
The action, by the American Federation of State, County and Municipal Employees and the Service Employees International Union, shows the seeds of discord behind the optimistic talk at a White House conference on health care this week.

Unions had value, many decades ago when workers were exploited. At what point did they morph into de facto temp agencies, rationing workers to companies under the mistaken impression that they still have employees?