And they are much more skeptical of the very idea of having immigration limits, whereas the public - again, independents and Democrats, as well as Republicans, although not necessarily all in the same proportions - have a much stronger sense of the American government and American law having responsibility to Americans specifically rather than to people around the world. So the polarization is up versus down, not really right versus left.

But it's more an up-versus-down issue because the research has shown that opinion leaders, whether they're elected officials, journalists, business leaders - it's academics, religious leaders - they have dramatically different views on immigration. A

But the other audience, I think, is people in Central America because since last summer, they've been running ads down there - the United States government has - don't come, it's dangerous. You will be immediately deported. That's literally what it says in Spanish.

Well, enforcement theater is OK if it's reality theater. In other words, obviously, you want to make it clear, you want to make people see that the law is being enforced.

Of 472 civilian occupations defined by the Department of Commerce, only six are majority immigrant (legal and illegal). These six occupations account for 1 percent of the total U.S. workforce. Many jobs often thought to be overwhelmingly done by immigrants are in fact majority native-born: 51 percent of maids are U.S.-born, as are 63 percent of butchers and meat processors, and 73 percent of janitors.

But the question is - are we deporting a couple hundred people for show or are we actually making a serious effort to remove everybody who's got a final order of removal? When I say enforcement theater, what I mean is a kind of pretend enforcement.

The effects of illegal immigration aren't that different from those of legal immigration —an illiterate Central American farmer with a green card is just as unsuited for a 21st-century economy as an illiterate Central American farmer without a green card.