From the campaign trail to the White House, Mr. Trump has directed much of his focus to rebuilding American jobs and industries. In April 2017, Mr. Trump signed a “Buy American and Hire American” executive order, with the goal of promoting the use of “American-made goods and to ensure that American labor is hired to do the job.”

Mr. Trump has put a particular focus on revitalizing American manufacturing, which he says has been decimated by cheap Chinese labor and materials.

That has Democrats questioning why the agency is not being more aggressive in going after American companies that manufacture their goods in China.

“Many companies that manufacture at home are already treading water,” Rohit Chopra, a Democratic F.T.C. commissioner who disagreed with the decision, said in an interview. “American companies shouldn’t lose out to corporate cheaters who lie on their labels.”

Mr. Brown, who is considering running for president, said the agency’s penalty did not match the severity of the companies’ behavior.

“If companies that break our laws do not face financial penalties, then our American manufacturers are severely undermined,” Mr. Brown said. “We need stronger enforcement by the F.T.C. and greater transparency when it comes to the commission’s actions to crack down on these violators.”