Ross Perot, who died Tuesday, has not been much in the news in the past few years. But his ideas surely have. His staunch opposition to the North American Free Trade Agreement in the 1990s found a powerful echo two decades later when Donald Trump ran for the presidency calling for a wall on the Mexican border and dismissing Nafta as “perhaps the worst trade deal ever made.”

“We do the world’s dumbest trade agreements,” Mr. Perot told Vice President Al Gore in a televised debate in 1993. “You go back to the agreements we’ve done all over the world, you’d be amazed that adults did them.” Mr. Perot’s call for using tariffs, not Nafta, to force Mexico to improve its workers’ standard of living is not unlike President Trump’s attempt to use tariffs to force Mexicans to stop migrants seeking to come to the United States.

Many of Mr. Perot’s predictions about Nafta’s impact — notably his claim of the “giant sucking sound” Americans would hear as businesses shuttered operations in the United States — proved either wrong or overstated. Paradoxically, however, his skepticism about lowering trade barriers has proved prescient.

Some industries indeed relocated operations to Mexico or added new capacity there following Nafta. Mexico added many manufacturing jobs in the first several years after the deal. But in the five years after Nafta came into force in 1994, manufacturing employment in the United States increased, too, by 800,000. Many got their jobs from a surge in exports from the United States to Mexico.