A band I was in years ago had a song titled, "Sheet Rockers vs. Aluminum Siders," about a fight our singer saw at work on a construction site.
I was reminded of it earlier today, when members of the International Longshore and Warehouse Union (ILWU) stormed the Port of Longview, Washington, where they held security guards hostage, blocked a train, and destroyed property, damaging railroad cars and dumping grain. They were protesting the hiring at a grain terminal by the employer, EGT, of a contractor employing workers belonging to a different union, the Operating Engineers.
Such union turf battles are not novel. What is unusual about this one is that it doesn't involve the ubiquitous Service Employees International Union (SEIU), which in recent years has picked fights with UNITE-HERE, the California Nurses Association, and its former affiliate, National Union of Healthcare Workers. And now members of a health care workers local in Michigan are trying to disaffiliate from SEIU, which a local spokesman said, "seem to only be interested in collecting dues from us."
While SEIU's unusually large number of fights with other unions is largely due to the efforts of its recent former president, Andy Stern, to centralize his authority, inter-union fights are still nasty in a way rarely seen between market competitors. That's probably because for unions, the stakes are higher. (Current SEIU head May Kay Henry has largely continued Stern's policies.)
Under current labor law, unions enjoy the privilege of monopoly representation of all workers in a bargaining unit, which makes representation an all-or-nothing proposition -- you can't fight for market share when the market is indivisible.
For more on SEIU's fights with other unions, see here.