Thomas Donlan of Barron’s searches for reasons why Bernie Sanders was able to beat Hillary Clinton in Michigan’s recent Democratic presidential primary.

Both must be keenly aware that something went wrong for Clinton in the Michigan campaign. In debates and campaign speeches, she made it a cornerstone of her campaign to blame state Republican skinflints and tax cutters for the Flint water crisis. But exit interviews and polls showed that many Michigan Democrats were much more sensitive to Sanders’ attacks on her past embrace of trade agreements.

This is a problem for both parties and in many states. Too many Americans prefer to blame what Sanders calls “disastrous trade agreements written by Corporate America” for economic problems that actually were caused by advances in technology and liberty poorly understood by politicians. We can look forward to more wild claims about trade deals, if the path to electoral success is to tell the voters what they want to hear. …

… At all levels, from the factory floors to the executive suites, the U.S. auto industry, like other American businesses, lived in a dream world of American autarky—a closed circle of self-sufficiency, reinforced by government regulation and unchallenged by competition. They and their workers and the workers’ unions were done in by the new age of globalization, not by trade agreements that ratified reality. …

… Detroit was the epicenter of an industrial earthquake that was felt from Maine to Oregon, from shoemaking to mining, from 1970 to the present. In such places, there is often a focus on the old jobs that too often becomes a focus on failure or a focus on returning to the good old days.

Making the U.S. a winner, however, does not mean walling off the country with tariffs, quotas, and trade barriers. Nor does it mean bending or breaking trade agreements that have helped to create jobs in other sectors. Making the U.S. a winner means continuing to change the American economy, American business methods, and American workers’ skills, and to change them fast enough to keep up with and surpass the competition.

Leaders who tell us that jobs are lost because of trade pacts and unfair competition are wrong, and they make it doubly likely that more jobs will be lost.