Matthew Yglesias has a good article on what’s wrong with the concept of “guest worker” programs:

The details of these proposals vary quite a bit and, as ever, the details are important. But all varieties of the concept share some factors in common. Unlike regular immigrants, guest workers are only allowed into their host country for a limited period of time and have no chance of ever becoming citizens. Guest workers are also typically the “guests” of some specific employer who’s agreed to sponsor their stay in the United States. This leaves them unable to bargain credibly with their employers, start small businesses of their own, or even just take risks around the workplace that stand some chance of getting them fired.

If you’re an employer, this is ideal. You have an utterly captive work force, unable to negotiate with you or even really complain. A work force that’s utterly under your thumb because you cannot only fire them but, in effect, have them deported. Needless to say, the prospects of such a work force unionizing are nil. Consequently, they have an even more negative impact on working-class wages than do regular immigrants.

[…]

Historically, migration to this country has mostly been unlimited. That era came to an end for good and bad reasons in the 1920s, but under modern conditions we almost certainly can’t return to the old ways. But the restriction era, in both its pre- and post-reformed versions has always tried to hold true to the basic vision of America as “a nation of immigrants.” The essence of this vision is the expectation that people who come to American will become Americans — applying for citizenship when eligible and starting families here whose children will be, by right, citizens of the country in which they were born. This vision is good for immigrants, of course, but importantly it’s integral to our shared identity as a nation.

Guest workers would undermine this vision of America, creating a semi-permanent underclass of hired hands who are neither citizens, nor on the path to citizenship, with no incentive to seek assimilation or for the native-born to treat them as equals. Sectors of the economy featuring large numbers of guest workers really would become jobs Americans “won’t do,” the fields in which they work stigmatized as beneath the dignity of proper Americans.

That seems right to me. Of course, it may be that there are would-be “guest workers” who don’t want to become Americans, but would like to come here, work, save some money, and then return to their home country. After all, as Camassia pointed out, it’s not as though people are generally eager to pull up roots and leave their homes. Many, if not most, would, other things being equal, probably prefer to stay in their country of origin. But a program that forecloses the possibility of becoming a citizen certainly is open to Yglesias’ objections.