The previous poster said, "You are doing something wrong." You just told him or her what we're doing wrong.

You are, apparently, unaware that a U.S. citizen has an absolute legal right to enter the United States at any time, with or without identification. Obviously the person will have to establish, to the satisfaction of border control agents, that he or she is indeed a U.S. citizen, but identification is not actually required.

It's not exactly duress, but it's not the (largely imaginary) ideal of a contract freely negotiated between two equally powerful parties, either. Most employment contracts are standard "take-it-or-leave-it" documents that qualify, legally, as "contracts of adhesion." The previous poster's "Sign this or you won't be able to feed your family" is pretty much right on the mark.