My aunt argued against it. Why she argued against it and why she was wrong provides the core of a Tea Party immigration policy that is in the United States' interest, comprehensive, and humane.
There are people who fall in love from afar. My father is like that with the USA. My family's tale of immigration starts with my grandmother running from an intolerable personal situation and my grandfather following her. My two aunts were born in the US. My family returned to Romania in a case of pretty bad timing, just in time for the bottom to drop out as the Great Depression started soon after. My father grew up on stories of America and what it was like there and when my aunts became adults, they eventually got their US passports and left.
The soft costs of immigration to the immigrant and family ripple across a generation or two. There is a loss of social context, a feeling of not entirely belonging. You're the outsider, the stranger. Both cultures are home but neither culture entirely fits. Unless you are like my grandmother and desperate or like my father and in love, these soft costs dominate the equation and people just don't move very often.
Essentially my father was an american long before he set foot on US soil. He loves this country, became naturalized, learned english, had a long career as a civil engineer, and did his best to make America a better place. He's the sort of immigrant that contributed far more than he took and is a significant chunk of the conservative movement. He's also a minority of immigrants crossing the border today. Such love affairs have always been a minority but they are an important minority to recognize and embrace because they falsify the narrative of the Tea Party's enemies that it is cruel and unfeeling and only interested in simplistic solutions that have no soul.
The desperate, on the other hand, are dangerous. Desperate people can swamp a boat, collapse a bridge, trample people to death. Talk to anybody who does work in crowd control and they'll tell you desperate people in large numbers can be scary dangerous. The crowd control professionals have all sorts of multi-layer strategies to prevent, reduce, channel, and contain the consequences of crowds gone wrong (desperation is shorthand for a number of emotions, the common point being that they shut down rational thought and good sense).
Here is where the border fence comes in but it has to come in as a part of a multi-layer strategy that starts long before the fence because, like any crowd control person can tell you, any fence can be overwhelmed and if that's all you've got, you're in trouble before the first person arrives.
The first thing to do is source identification.
The numbers bring a simple matter into focus. If you solve the problem of illegal immigration from Mexico and you've both solved well over half the US problem but you've also created a natural buffer to absorb economic migrant that is closer and more culturally compatible for another quarter of the illegal immigrants. Every Guatamalan that settles in a Mexico that is much better off instead of the longer, harder trip to the US is a Guatamalan that never shows up to even try the US border. Making Mexico better off helps reduce the problem. It's the first line of border defense.
This is a border defense proposition that would scramble the existing political configuration. Specifically, it would be be very difficult for the Catholic Church to be against such an initiative. It would also cause hispanics to reassess the humanity and compassion of immigration opponents. It also fits very well as a Tea Party initiative because the fiscal effects of such an initiative would overwhelmingly be positive in reducing transfer payments on net.
Searching how to configure all the phases, from pre-crossing, crossing, and on to post-crossing efforts to increase effectiveness and reduce expense would make for a more effective immigration system and ideally one that both cost less and promoted fewer injustices.