The Fence will not work. No fence will work. The Great darn Wall of China will not work. Do not build a fence. It will not work. They will come anyway. Over, under, or through. […] Anyone who says a fence can fix this problem is a demagogue and an ass.

Molly Ivins (1944–2007) American writer, political columnist [Mary Tyler Ivins]

Essay (2006-03-30), “Immigration 101 for Beginners and Non-Texans,” Creators Syndicate column
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Included in Progressive magazine's memorial article (2007-02) to Ivins, referencing their 2006-06 issue, edited down slightly:

The Fence will not work. No fence will work. The Great darn Wall of China will not work. Undocumented immigrants will come anyway. Over, under, or through. Anyone who says a fence can fix this problem is a demagogue and an ass.