From a reader in response to the Zeitgeist post below:

Jonah,
Amen.
Immigration is basically a plumbing problem – our border leaks. When
you have plumbing that leaks, you fix the leak before you start
cleaning up your house. Build a fence and stop the leak, then decide
how to clean up.
Note that the leak is cause by a pressure differential across the
souther border – lots of people want to come here. (Compare to
northern border). Economic opportunity here far exceeds that in
their own country, and there is little risk of associated with coming
here illegally. So pressure builds to our south. Once the leak is
stopped, we can look at ways to equalize the pressure. Strict
enforcement and deportation would do it. Getting Mexico to reform
would help as well. I’m also fine with increasing legal immigration
through carefully regulated valves on our southern border.
Ironically, amnesty will only increase the pressure.
Yes, I am an engineer.