A woman walks past a sign displaying the dollar exchange rate at a bank branch in Mexico City, Mexico, on March 4, 2025. (Photo by Francisco Canedo/Xinhua)"The main effects of these policies now are creating wild uncertainty," said Wolf, highlighting that such unpredictability stifles investment plans, hampers the formation of trade deals and ultimately leads to a general malaise in economic activity.LONDON, March 20 (Xinhua) -- U.S. President Donald Trump's trade policy is "entirely without precedent in the history of trade policy anywhere," said a British economics commentator."It's completely mad. It doesn't represent a coherent approach to trade policy in the slightest. It's erratic, unpredictable, ill-focused, and much of it has nothing to do with trade policy," Martin Wolf, chief economics commentator at the Financial Times, told Xinhua in an exclusive interview.Wolf expressed his astonishment at the U.S. administration's erratic approach, noting that the idea of imposing a tariff overnight, canceling it the following morning, and then threatening to reimpose it is beyond imagination.Such actions are a violation "not just of every rule in international trade which has been established since the General Agreement on Tariffs and Trade in 1947," but also "a violation of any sensible trade policy," Wolf said."The main effects of these policies now are creating wild uncertainty," said Wolf, highlighting that such unpredictability stifles investment plans, hampers the formation of trade deals and ultimately leads to a general malaise in economic activity.Speaking about the impact on the U.S. economy, Wolf noted that in the short to medium term, the U.S. economy will face higher import costs, making Americans poorer and driving up prices, as domestic production cannot replace imports overnight.In the long term, Wolf said, while some U.S. firms might invest in import substitutes, such moves would be "risky," as Trump's four-year presidency contrasts with the longer investment horizon needed for major factories. If Trump's policy is overturned after four years, "a lot of manufacturers are left high and dry with products that aren't competitive."In addition, investing in import substitutes could divert resources from more competitive sectors, like export industries, shifting production to less efficient areas, which is unwise, said Wolf.Customers shop at a Target store in Rosemead, Los Angeles County, California, the United States, on March 4, 2025. (Photo by Zeng Hui/Xinhua)The benefits of Trump's trade policy on the overall U.S. labor market will also be pretty small, the economist said. "There might be a net increase in industrial jobs at the expense of jobs in other sectors, for instance, service sector."Also, Wolf pointed out that Trump's tariff decisions seem to have nothing to do with trade policy. "In the case of his policy vis-a-vis Canada, for example, Trump's talking about drugs and illegal immigrants, which, to my knowledge, have never been introduced as part of trade policy discussions.""There may be exceptions, but certainly not so far as I know with any major country. So this style of trade policy is completely unprecedented," he said.