Democrats often pillory Republicans for their economic errors. From the 1930s on, they reminded Americans of Herbert Hoover’s Great Depression. In 1960, they blamed Dwight Eisenhower for slow growth. In the 1980s, they decried the “trickle-down” policies of Ronald Reagan. And today, they excoriate the damage caused by the North American Free Trade Agreement passed under… Bill Clinton.

Even Hillary Clinton treats the accord with a warmth she normally reserves for Kenneth Starr. She never misses a chance to denounce what she calls “the shortcomings of NAFTA,” or to insist she was always against it. But she has to deal with Barack Obama, who often gives the impression that his opponent’s name is Hillary Nafta Clinton.