If you support free markets, Mary Anastasia O’Grady’s Wall Street Journal op-ed makes for frightening reading:

The U.S. hasn’t elected a genuinely protectionist president since Herbert Hoover, and for most of the last 80 years a rough bipartisan consensus has held that free trade is in the American national interest. The erosion of that consensus is reflected in the gulf between John McCain and Barack Obama on trade, which is probably the widest division at the presidential level since the 1920s.

Mr. Obama opposes the Colombia and South Korea agreements, for the same reasons cited by other Congressional Democrats. In the last presidential debate, Mr. Obama pointed to violence in Colombia against labor unions. The politically independent Colombian attorney general says violence against union members has come down sharply under President Alvaro Uribe, but Mr. Obama says that’s insufficient.

He also opposes the South Korea pact, which would remove auto tariffs in both directions and end South Korea’s use of nontariff barriers to protect its domestic markets. Mr. Obama says the U.S. buys “hundreds of thousands of cars” from South Korea and “we can get only 4,000-5,000 into South Korea.” The Democrat wants assurances that the imbalance in auto sales will end. The Obama campaign declined to tell us whether he supports the Panama FTA or trade negotiating authority.

More generally, Mr. Obama says he would change the way the U.S. negotiates trade agreements. Instead of focusing mainly on removing barriers to the movement of goods and services, he would use the agreements “to spread good labor and environmental standards” to the rest of the world. He voted against the Central American Free Trade Agreement (Cafta) in 2006 and says he will oppose others that do not have strong-enough labor and environmental provisions.

Trade within Nafta topped $930 billion in 2007, more than three times what it was in 1993, the year before Nafta was implemented. Mr. Obama nonetheless believes Nafta has hurt Americans because it does not contain provisions to force our trading partners to adopt U.S. labor and environmental standards. He says Bill Clinton’s Nafta accord was “oversold” to Americans and that he would seek to amend it so that it “works for American workers” — and that he’d do so unilaterally if Canada and Mexico refuse to cooperate.

This position became a source of controversy during the primaries, when a Canadian diplomat quoted Obama economic adviser Austan Goolsbee as saying privately his candidate’s words were for U.S. domestic political consumption and wouldn’t be implemented if Mr. Obama won. The Obama campaign said Mr. Goolsbee’s comments were taken out of context and reiterated Mr. Obama’s intention to renegotiate Nafta. Neither Canada nor Mexico has shown an interest in such a negotiation, which might mean higher costs for their producers.