Both President Obama and the bipartisan group of senators proposing comprehensive immigration reform insist that unauthorized immigrants must move to "the back of the line." But what is the line? In fact, there's are many lines - limits on overall immigration but also limits on immigrants from any one country. And some believe that's the problem. Countries that provide big numbers of immigrants have a line that is so long it might encourage more unauthorized immigration.
GUESTS
Mae Ngai, Professor of History, Columbia University
