Hillary Clinton promises to start renegotiating Nafta in her first 100 days as president. Barack Obama would use the threat of opting out as a ''hammer'' to demand strong labor and environmental standards in Mexico.
In the United States primary elections, the Democratic candidates have heaped blame on the 14-year-old North American Free Trade Agreement for the plight of unemployed workers in declining industry towns who have lost their jobs to global competition.
But what they are really talking about when they bash the agreement, which lifted trade and investment barriers among Canada, the United States and Mexico, is trade with Mexico.
''Nafta was our first debate after World War II on globalization and it still carries a high charge because of that,'' said Harley Shaiken, director for the Center of Latin American Studies at University of California, Berkeley. ''To reject Nafta is not to reject the global economy. It is to say that there are better ways to integrate and adapt to it.''
But the pledge to rewrite parts of Nafta is a lot more complex than either candidate has publicly conceded. How would tighter labor and environmental standards be enforced? And would that restore lost manufacturing jobs?
The attack on Mexico comes as a bit of a surprise, since there is little doubt that the rise of Asia, particularly China, has accelerated job losses in the United States faster than Nafta did.
Still, the rhetoric carries a strong punch - particularly when iconic American brands pick up and move to Mexico.
Like Hershey's chocolate. Earlier this month, Teamsters President Jim Hoffa went to Reading, Pennsylvania, to visit what the union called ''Nafta victims'' - 260 workers in a Hershey plant that is moving to Mexico by the end of the year. ''These so-called trade deals are killing American jobs,'' Hoffa said. ''They aren't about trade, they're about helping companies move their factories to countries with cheaper labor.''
In theory, stronger labor and environmental standards would raise the cost of doing business in Mexico and might make companies think twice about moving. Still, with the average hourly manufacturing wage in Mexico about 13 percent of the U.S. average, according to the Bureau of Labor Statistics, Mexican labor is still very cheap.
Then there is the problem of enforcing those standards. Under Nafta's labor and environmental side agreements, there are no effective sanctions against companies that break the law or governments that do not enforce it.
Some opponents argue that at the very least, those agreements should be subject to the same kind of arbitration and sanctions that disputes over trade or investment barriers now face.
But even those might not have much effect. Nafta trade disputes drag on for years and are not always enforced.
Another route might be to fine violating companies or even bar imports from them. But that could backfire.
Under Nafta, industries like autos have become highly integrated. Parts move back and forth across the border several times as subassemblies are put together and finally end up in auto plants in the United States.
Halt that process anywhere along the regional assembly line, perhaps for a labor violation, and the American plant and its workers gets hit.
''Nafta is not going to go away,'' said Jeff Faux, a fellow at the Economic Policy Institute, who opposed the agreement when it was being negotiated in the early 1990s. ''You can't put the toothpaste back in the tube.''
Mexico's conservative government has rejected the idea of renegotiating Nafta. But if the agreement were opened up, Mexico would present its own set of demands, perhaps on easing legal migration or protecting corn farmers.
''If we are going to have a serious negotiation, it's not going to be one-sided,'' said Luis de la Calle, a former Mexico Nafta negotiator who is now a political consultant. ''Let's put labor and the environment back in Nafta but in exchange for what?''
American analysts question whether a new president would want to spend political capital on reopening Nafta when there are issue likes health care and the war in Iraq to be tackled.
And the focus on environment and labor rights ignores other changes inside Mexico. A strong environmental movement has developed, which has put multinational manufacturers on their guard and pushed the government to inspect industrial polluters.
Indeed, American baby boomers, rather than American factories, are unwittingly at the center of Mexico's fiercest environmental debate now.
Local activists have been fighting the pell-mell development of Mexico's coastline - much of it driven by the demand for retirement homes and time shares for retiring Americans.
In labor, the picture has changed less. Export plants still mostly recognize compliant sham unions. But even if a reworked Nafta could strengthen labor rights. Multinational corporations in Mexico now hold the same trump card they hold in the United States: the threat to move to a cheaper country, like China.
Indeed, analysts on all sides argue that if anything concrete is to come out of the campaign's Nafta-bashing, it should be a much broader approach to the relationship with Mexico and Canada.
''They have put so much attention on Nafta that the next president will have to do something,'' said Jeffrey Schott, a senior fellow at the Peterson Institute for International Economics in Washington.International Herald Tribune
