I don't know about "no such thing", but I know this. I lived in several European countries, courtesy of Uncle Sam, in my working days, that had guest worker programs. The offspring of those guest workers, who never left, are now home-grown terrorists and thugs, rioting and assaulting their "hosts" in the streets of those European countries.
All of those Islamist fanatics in Cologne and Salafi lunatics in Hamburg-plotting Sept. 11th Part II as we speak-are the progeny of people who were "invited" into Germany as "guest"-workers.
Why does our government insist upon repeating the same failed experiment again and again?