Donald J Trump sent shivers across the Japanese auto industry on Friday after warning Toyota on Twitter that he would impose a “big border tax” on the company if it built a new plant in Mexico.

It appeared to be the first time he had taken on a foreign company for plans that did not directly involve the United States.

The effects were immediate: Shares in Toyota and other carmakers fell in trading on the Tokyo Stock Exchange on Friday. And Japanese government officials hustled to respond to the rhetoric with soothing reminders of the jobs that the country’s auto manufacturers had created in the United States.

“Toyota itself has tried to be a good corporate citizen in the US to date,” said Yoshihide Suga, chief cabinet secretary to Prime Minister Shinzo Abe.

Daily Gendai, one of Japan’s leading tabloid newspapers, declared in a front-page headline that “Trump tries to smash Toyota,” and another tabloid, Evening Fuji, hinted at a coming battle with its headline, “Trump vs. Toyota.”

Throughout his presidential campaign, Trump said he would punish American companies that moved manufacturing plants offshore. Soon after his election, he claimed credit for persuading Carrier, the air-conditioner company, to keep 1,000 jobs in Indiana that it had previously planned to move to Mexico. And he thanked Ford Motor on Twitter this week for abandoning plans to build a small-car assembly plant in Mexico that Trump had repeatedly criticized.

Trump’s Twitter post was not entirely accurate. He said Toyota would build a new Corolla factory in Baja, but the company is actually planning to build a new plant in Guanajuato, Mexico. (It already has a factory in Baja.) More significant, Toyota’s new plant in Mexico will not replace any of its 10 factories in the United States, where the company employs 136,000 people. The company said it had invested about $21.9 billion in the United States.

“I think being fair is not really in the playbook of the president-elect,” said Takuji Okubo, managing director and chief economist at Japan Macro Advisors. Toyota builds Corollas in Cambridge, Ontario, as well as in Blue Springs, Miss. No workers in either of those plants will lose jobs, and when Toyota opens the new facility in Mexico, the company plans to shift the Canadian workers to making small RAV4 sport utility vehicles.

According to Hiroshige Seko, Japan’s minister of economy, trade and industry, Japanese carmakers manufactured about 3.86 million cars in the United States in 2015, up from 1.5 million in the 1990s, and employ about 1.5 million people. In response to a question about Trump’s post at a meeting of the Japan Automobile Manufacturers Association, Akio Toyoda, president of Toyota, said the company would not change its manufacturing plans in Mex-ico. “I don’t know yet exactly how, but, regardless of who becomes president, our business is about being good corporate citizens,” Toyoda said, according to a repo-rt in Japan Today. “And by becoming good corporate citizens, we are facing the same goal of making America strong. And so we will continue to do our best.”

Even though there are only two weeks left to the inauguration, some analysts suggested Trump might still be in campaign-promise mode. “At the moment, it’s quite unclear whether Trump actually will push this policy after assuming office,” said Yoshio Tsukuda, founder of Tsukuda Mobility Research Institute, an auto industry research firm. “Right now we don’t know if he is just bluffing or serious.” But others said some of Trump’s words could spur changes on their own. “I think the threat alone can actually force companies to behave in a more Trump way,” Okubo said. “So I think regardless of whether the border tax would actually be implemented, I think he will continue to use the threat to pressure companies.”

While Trump singled out Toyota on Thursday, analysts said that his views on trade clearly extended beyond a single company. “The US is no longer a champion of free trade as a nation,” wrote Genki Fujii, visiting professor at Takushoku University in Tokyo, in a column in Evening Fuji.

In comments to the Japanese broadcaster NHK, Takao Shindo, president of Nippon Steel & Sumitomo Metal Corporation, expressed concerns that Trump would repeal the North American Free Trade Agreement, which affects Japanese manufacturers with plants in Mexico shipping to the United States. These companies “will face a tough situation,” Shindo said.

Some analysts said that once Trump understood what Toyota was doing with its plants, he might back down. “Toyota still is expanding local US production in the long term,” said Takaki Nakanishi, an independent auto industry analyst in Tokyo. 

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