Mexifornia
I'm with Cathy Seipp -- an immigrant herself (from Canada...wooo!) for closing the borders. Smart piece about this up on her site:

I am generally pro-immigrant, and would be even if I weren't an immigrant myself. But Victor Davis Hanson's book "Mexifornia" was key to convincing me that we have to get serious about closing the borders and quitting our reliance on cheap illegal immigrant labor. As Hanson points out, besides the obvious problems we have in California (and other border states) with overcrowded schools and hospitals, etc., the situation is exploitative of the immigrants themselves.

I'm not as unsympathic as many are, by the way, to employers who are less than scrupulous about hiring only legal workers, because I can't see how it's an individual's responsibility to enforce laws that the federal government ignores. Nor am I unsympathetic to illegal immigrants, any more than I'm unsympathetic to people trying to get on a crowded elevator. But at some point you've got to shut the door and those people are going to have to wait for the next one, or we're all going to be stuck on the ground floor.

The Wall Street Journal has an excellent article today (unfortunately available only to subscribers, so I can't link) that's a useful reminder of why we have an illegal immigration problem: Mexican society continues to be remarkably regressive and unfair; the rich own practically everything, and the poor practically nothing, with little hope of rising to the middle class -- which basically doesn't exist anyway in our wonderful multicultural neighbors to the south. The typical L.A. busboy or cleaning lady is about 10 times better off than the typical Mexican peasant. It's hard to blame people for wanting to escape miserable circumstances.

Still, I think we've got to close the border. The alternative is to realize that an open border is no border, in which case we face facts and annex Mexico as part of the United States. Make it a territory, like Puerto Rico.