In the late 19th-century and early 20th-century, trade unions:
1) Were in fact alliances of the employed and unemployed (unemployed former workers and retired workers, not to be confused with the lumpen);
2) Provided social services;
3) Showed a lot less hesitance towards calling strikes; and
4) sometimes posed political questions.
Out of all these came the "One Big Union" and "socialist industrial union" concepts, which didn't unite workers on merely a sectional basis.
Today, a tred-iunion (I'm using Russian here to describe "yellow" unions, "business unions," etc.) caters only to its particular section of the working class, doesn't provide social services (except perhaps entertainment for bureaucrats :rolleyes: ), pays lip service to the very concept of strikes (signing no-strike deals, for example), never poses political questions, and even organizes sometimes on the basis of craft and not trade.
Heck, a tred-iunion doesn't perform the functions of "[URL=http://www.marxists.org/archive/marx/works/1880/05/parti-ouvrier.htm]wor...' statistical commissions[/URL]" to check on the business figures of the capitalists.
Back in the 1920s, Trotsky had a very interesting proposal to save the Russian economy (including the enhancement of the statistical function): incorporate the unions into the state structure (similar to what Chavez is trying to do right now in Venezuela). In Germany, the ultra-left KAPD stated that "the unions are thus, alongside the bourgeois substructure, one of the principal pillars of the capitalist state." A generalization would be wrong, of course, since proper trade unions should remain independent of the bourgeois state.
However, in today's context, since a modern tred-iunion resorts to negotiation and mediation (between the bosses and the union rank-and-file, not "on behalf of the employees"), should that kind of organization be incorporated into the bourgeois state apparatus and compliment, say, labour courts?
Basically, this means that collective bargaining should become a bourgeois state function, a "free" legal service.