In today's NYT, Krugman says a guest worker program is a bad idea:
Meanwhile, the bill creates a guest worker program, which is exactly what we don’t want to do. Yes, it would raise the income of the guest workers themselves, and in narrow financial terms guest workers are a good deal for the host nation — because they don’t bring their families, they impose few costs on taxpayers. But it formally creates exactly the kind of apartheid system we want to avoid.
I must say that this leaves me confused. Krugman is the author of the justly famous "In Praise of Cheap Labor," which, correctly in my view, chastised opponents of globalization for not understanding that the poor working conditions and low wages they see in developing nations would be only worse in the absence of the trade and outsourcing the critics rile against. But now he is against a guest worker program because the labor conditions for these workers may not be up to some high standard which these guest workers would never hope to reach in their home countries?
What am I missing?