Government failure, private success
by Michael D. Tanner
http://www.cato.org/pub_display.php?pub_id=4827
"While the response to hurricane Katrina has uncovered failures of government at every level - federal, state, and local - it has also revealed again the amazing generosity and effectiveness of America's private charitable efforts."

I've often thought exactly what this article says. You can't force people to be charitable by taxing them.