The president’s tariffs against China, Mexico and Canada eliminated a trade exemption used by low-cost retailers.

Fast-fashion retailer Shein and online dollar-store Temu, both of which sell products ranging from toys to smartphones, have grown rapidly in the U.S. thanks in part to the "de minimis" exemption enabling them to keep prices low.

President Donald Trump’s sweeping tariff threats have been touch and go. As it stands currently, the 25 percent tax on goods from Mexico and Canada is on ice for a month, but a 10 percent tariff on Chinese goods is set to take effect on Tuesday, via an executive order of questionable legality.