I was listening to NPR the other day about a mining town that lives almost exclusively off the mining of Borox. The british controlled company, Rio Tinto, recently blocked union workers from their jobs. They replaced them with workers from other Rio Tinto locations. They did this as a result of an ongoing dispute with the unions. It then occurred to me, is this not a simple way (or at least impossible to prove intent) to skirt union laws? All you have to do is overhire somwhere else in response to a fight with a union, fire the union workers, and then replace them with "_existing_" workers, thereby breaking no law? If this is the case, unions are toast.