David Kramer, at Lew Rockwell blog:

“You know what an “illegal” immigrant worker is, don’t you? It’s someone who voluntary decides to move from one piece of land on the planet Earth to another piece of piece of land on the planet Earth because he or she knows of a person at that second piece of land on the planet Earth who wants to voluntarily exchange with him or her a medium of exchange for his or her labor services—but wasn’t given permission to by a third party with a gun (i.e., the government).”