Barack Obama says Pennsylvania's rural voters are "bitter" over lost jobs. Hillary Clinton bellies up for a beer with a whiskey chaser in a working-class Indiana bar. So go the latest primaries, with voting scheduled for next week and another televised debate tomorrow. One real issue that might come up is the free-trade deal, like the deal with Colombia, which Democrats have scuttled, at least for the moment. Both Obama and Clinton have publicly promised to renegotiate NAFTA, while surrogates were reassuring Canada they supported free trade. They're both opposed to President Bush's trade pact with Colombia, too. But Bill Clinton's a big supporter. What are the pros and cons? Why do Bill and Hillary Clinton disagree? Is free trade America's only choice in the global economy?