In a bid to woo blue-collar voters in Ohio before Tuesday's presidential primary, Barack Obama and Hillary Clinton trashed free trade during their debate this week in Cleveland.

Sen. Clinton denounced the North American Free Trade Agreement (Nafta) as "flawed" and blamed it for closing factories in Ohio and upstate New York. Sen. Obama claimed that "if you travel through Youngstown and you travel through communities in my home state of Illinois, you will see entire cities that have been devastated as a consequence of trade...