"It's really possible to create great quality pieces that stand the test of time, that are beautiful," Ivanka Trump told The Wall Street Journal when her clothing line launched in 2012, "in more affordable price brackets."

It's possible largely because they're made in China and Vietnam.

Trump's father, President-elect Donald Trump, suggested on Sunday that he wants to cut this supply chain, warning companies that shuttling work overseas could soon bring stiff penalties. "Any business that leaves our country for another country, fires its employees, builds a new factory or plant in the other country, and then thinks it will sell its product back into the US . . . without retribution or consequence, is WRONG!" he wrote on Twitter. "There will be a tax on our soon to be strong border of 35% for these companies ......"

Such a tariff could drive up the prices of Ivanka Trump's products, as well as the cost of her father's Donald Trump-brand suits, shirts and ties, which are also made in China. (Trump told CNN in May that he outsourced the labour to remain competitive.) Companies beyond his familial inner circle, of course, could meet the same fate.

Ivanka Trump's $US100 million clothing line is stitched together predominantly in the Asian countries under a licensing agreement with G-III Apparel Group, a New York manufacturer that supersized its Garment District business by sending work abroad. It's unclear how much money outsourcing saves G-III and, by extension, Ivanka Trump, but China's hourly minimum wage is equivalent to less than $US3 ($4).

A black Ivanka Trump wrap dress on Nordstrom's website is described as "imported." So is a pink midi number, a metallic-knit sweater and a faux-fur coat .

This arrangement is the norm in the US apparel industry. Manufacturing jobs in the United States have dropped nearly 40 per cent since their 1979 peak, thanks to cheap labour overseas and the rise of automation. Today, two per cent of US apparel is produced in the country, according to Alvanon , an apparel consulting firm.

Marshal Cohen, chief industry analyst of the NPD Group, a market research company, said a 35 per cent tariff probably wouldn't kill the Trump daughter's business, though it could price out some of her corporate-ladder-climbing shoppers.

"The same time her prices are going to go up," he said, "so is everyone else's."

Job concerns

Ivanka Trump, meanwhile, might not be comfortable with the geography of her dealings. Forbes reported that she asked G-III last year if the company could move some of her label's production to the United States.

"There's been a major push by Ivanka on us," G-III executive Sammy Aaron told Forbes . "She's been proactive on the 'Made in America' thing." Since July, however, there has been no indication that Ivanka Trump and G-III have brought her clothing line to American factories.

Ivanka Trump, Aaron and G-III did not respond to The Washington Post's requests for comment.

Imposing 35 per cent tariffs on firms with international operations could cause more job losses, said Robert Lawrence, an international trade professor at Harvard's John F. Kennedy School of Government. About two-thirds of American imports are either parts of a product or equipment to finish a good, he said.

"To impose a tariff would be to severely threaten these global supply chains," Lawrence said. "All kinds of important retailers who serve American consumers use imported products from China. Their business would be disrupted, and employment in those businesses would be disrupted."

The Washington Post