I don't see why these people can't go back to their home countries and begin the same process that the rest of us non-US-citizens have to go through if we want to live in the US.
It seems like there are powerful groups that would prefer the law to be flexible as regards migration - but not flexible when it comes to IP law, for example, where they want to be able to fully exploit their patents, and to throw people in jail for torrenting a few films.