Chinese President Xi Jinping and President Trump have disagreed on trade. (Carlos Barria/Reuters)

Chinese tariffs could threaten business in thousands of U.S. counties that voted for Donald Trump in the 2016 presidential election, shrinking sales for soybean farmers and pork producers. But 15 of the 20 counties with the most jobs at risk supported Democrat Hillary Clinton, according to a new analysis from the Brookings Institution.

Blue states such as Washington and California, cradles of aerospace and wine production, stand to lose access to one of the world’s fastest-growing markets if the trade war between the United States and China escalates, said economist Mark Muro, who co-authored the report.

The Asian giant could slap tariffs on 234 American products, including airplanes and plastics, in response to American levies on roughly 1,300 Chinese goods. Such actions could jeopardize up to 2.1 million jobs, Muro said.

“High-tech and low-tech, industrial and agricultural, commodity and specialty production are all represented and put into play,” the Brookings researchers wrote.

Los Angeles County, a hotbed of plastics manufacturing, is home to the most local jobs vulnerable to Chinese tariffs (40,996), the Brookings data show. King and Snohomish counties in Washington state tie for second, both with roughly 39,000 positions, mostly in airplane manufacturing.

Boeing, which sells its planes to buyers worldwide, is Washington's largest private employer, with half of the company’s workforce located in the state. The Chinese tariffs have targeted smaller planes — not jumbo jets — but analysts said Boeing’s signature 747s could become a bargaining chip between the planet’s two largest economies. (The company declined to comment on the tariffs.)

“Having grown up in Seattle, I can attest to decades and decades of Boeing’s ebbing and flowing being hugely important to the region,” Muro said.

A trade war between the United States and China could jeopardize jobs in 40 industries, according to the Brookings report, with the positions at risk nearly “evenly distributed” across political lines. Fifty-two percent are in red counties. But Democratic strongholds tend to have higher concentrations of at-risk jobs. Fifty-eight of the top 100 counties that could suffer from tariffs are blue, Muro said.

Vegetable and fruit growers in California’s Central Valley could take a hit. San Diego County, where the report estimates 18,352 jobs are at risk, could miss out on car part and plastics exports to China.

Napa Valley’s wine producers, meanwhile, worry their sales could drop as well. (U.S. wine exports to China and Hong Kong grew by 10 percent in 2017, to $197 million.)

“Over the last decade, we have made tremendous progress in developing a loyal and enthusiastic base of Chinese consumers who enjoy California wines and appreciate their quality,” Robert Koch, president of the Wine Institute, said last week in a statement. “These tariffs put our products at a price disadvantage, and we urge swift resolution of this issue before long-term disruptions are felt.”

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