Mr. Trump has already imposed tariffs on imported steel and aluminum from several countries, and on $50 billion worth of goods from China, a country his administration says is violating the norms of international trade. The president appears set to complete a second round of tariffs on China, on as much as $200 billion in imports, and he has said he is willing to move quickly to a third round that would encompass all Chinese imports — including many everyday household items like apparel, electronics and other consumer products. And he has continued to threaten tariffs on cars imported from the European Union and Canada.

That has raised the stakes for American businesses, which face higher costs to source material and products from abroad and retaliation from other nations that has made it harder to sell into foreign markets.

Business owners have found sympathetic ears among lawmakers and the White House, but little action, prompting a more coordinated effort to try to show how tariffs hurt American consumers and businesses by raising prices.

“Our objective is to talk about that point,” said Brian Dodge, a senior executive vice president at the Retail Industry Leaders Association, “and make sure that there is no one left with the impression that tariffs are something that other countries pay.”

The coalition includes small business owners like Vivian R. Sayward, who owns Vivacity Sportswear, an athleisure maker in conservative San Diego, and who has been frustrated by congressional inaction. On a recent visit to Capitol Hill, Ms. Sayward wore clothing made in the United States by her company but stitched with Dryflex fabric imported from China. She used her outfit as a teaching tool, telling lawmakers and staff members where each thread and zipper came from, and warning how a new wave of tariffs on imported goods would make the clothes much more expensive.

The reaction to her visit from members of Congress and their aides, Ms. Sayward says, was, “We hear you, we understand, but we can’t do anything just yet.”