http://news.ft.com/cms/s/bf6dcbe2-c3da- ... 511c8.html

“Building walls doesn't help anyone build a good neighbourhood,� he said. “Taking away the possibility of obtaining driving licences for people who are working in legal jobs, who pay their taxes there, who send remittances home here, seems to us to be an extreme measure, particularly given the new understanding that we thought we had after the re-election of President Bush.�

Andrés Manuel López Obrador, mayor of Mexico City, supported Mr Fox's stance. He said the problem of growing immigration could be “resolved by encouraging development in Mexico and Central America, not by building walls and using the border control�.
I wasn't aware it was the responsibility of the United States to "encourage development" in other countries so they would not try to invade ours. These Mexicans are off their rockers!