SEIU and UNITE/HERE apparently believe that they will be able to organize immigrants - even illegal ones and guest workers - easier than they can US citizens. Dunno quite what their logic is since all that a business has to do to stop an organizing drive in its tracks is to fire the obvious union sympathizers. Legal? No, but it takes years for the case to make its way through the legal system and most workers don't have a big cushion of cash and need paying work NOW, not years from now. Guest workers would be closely tied to their employers and so easier for the employer to control.

There was an entry at FAIR earlier this week noting that some growers in WA state were legally importing Thai workers to do agricultural work and dropping the illegal aliens who had been doing it. From the Seattle Times article:

Controversy over continued use of illegal immigrants, coupled with what some growers believe is a looming labor shortage, make the imported temporary workers increasingly appealing, some growers say.
"I think foreign guest workers are the answer for now, until the next big thing comes around