[republicagal]

But does that difficulty really warrant the enormous cost?

Do the economic disadavantages of having illegal immigrants in this country really outweigh the costs of building a fence that would not prevent them from getting in, just make it "harder" for them to do so?

I'm not convinced. at all.

www.freetrade.org/pubs/pas/tpa-019.pdf

Worst case scenario: welfare state gets bigger, people react, get angry that so much money is being spent, and move to finally get rid of the darn thing.

[CowboyJay]

"Do the economic disadavantages of having illegal immigrants in this country really outweigh the costs of building a fence that would not prevent them from getting in, just make it "harder" for them to do so?"

Yes.