Such an appearance helps McCain burnish his foreign policy credentials. But trade can also carry great risks, especially in election battlegrounds such as Ohio and Pennsylvania where many voters blame trade deals for job losses.
Canadian officials are watching the election attentively, too. Obama, who four years ago declared NAFTA had been beneficial, recently talked about reopening NAFTA to strengthen enforcement of labor and environmental standards. McCain has been thumping Obama on that, arguing that such a step not only would hurt trade, but undermine the credibility of the United States abroad.
"You know what message that sends? That no agreement is sacred to him," McCain told reporters Thursday in Boston.
McCain's trip to Canada was announced Wednesday by the Economic Club of Canada.
An AP-Yahoo News poll conducted mostly in April found that most Americans have a negative view of trade agreements.
Of those polled, 64 percent said that increasing trade between the United States and other countries has hurt the economy, while just 22 percent said it has helped. Moreover, 54 percent opposed the federal government negotiating new agreements with other countries, as opposed to 43 percent who favored more agreements, though Republicans tended to be evenly split on the question.
McCain clearly recognizes the public antipathy, particularly in some Midwestern states where the economy is reeling. "They're hurting there in Ohio," he told fundraisers in New York earlier this week. "It's been tough and it's been hard."
But McCain has been pushing expanded training and educational programs to help displaced workers prepare for new jobs. And he maintains that without free trade, American businesses would have even more difficulties.
"Our exports are one of the only bright spots in our whole economic picture, we all know that," he said earlier this week.
McCain also has been making a vigorous pitch for Congress to pass a new trade deal with Colombia, which Obama opposes. The House blocked a vote on that pact, citing continued violence against organized labor in the country and differences with the Bush administration over how to help U.S. workers displaced by foreign competition.
McCain said Thursday that the fate of the Colombian agreement goes beyond trade.
"It is an affirmation or a rejection of the cooperation, friendship and enormous support that the Colombian government and people have given us in trying to stem the flow of illegal drugs into the United States of America," he said.
Asked if he was planning a trip to Colombia, McCain said his plans were in flux. "We're looking at a lot of different places that maybe I should go, so we have no definite plans," he said.
Still, NAFTA is the most contentious and most recognized trade deal and it figured prominently during the Democratic primaries.
Obama and Hillary Rodham Clinton both criticized NAFTA as they campaigned in Ohio, Pennsylvania and other industrial states where workers have lost jobs. Obama questioned whether Clinton had always opposed the trade agreement.
In his own 2004 Senate campaign in Illinois, Obama spoke of benefits to his state from NAFTA, though he also called for more aggressive trade protections for U.S. workers. Four years later, he declared, "I don't think NAFTA has been good for Americans, and I never have."
But he came under scrutiny after a leaked Canadian diplomatic memo suggested one of his advisers told Canadian officials not to take Obama's campaign rhetoric against NAFTA too seriously.
The adviser, Austan Goolsbee, said his words during the meeting with Georges Rioux, Canada's consul general in Chicago, were misrepresented.
Canadian opposition member of Parliament Bob Rae said McCain's speech suggests Canadian Prime Minister Stephen Harper's government is playing favorites in the U.S. presidential contest.
"It's hard not to wonder what this is all about given the previous history of this story and I'm sure he would not have come unless he was told by the government of the day that it was a good idea," Rae said. "It does put Canada in the middle of the campaign."
