"It totally incentivizes you to move out of the United States and build either in Canada or Mexico"

Plants in every direction shut down and moved their operations to Mexico, succumbing to the relentless pressure to cut costs in an age of globalization. Not EBW Electronics. As the decades passed, the family-owned business stayed put, on the eastern edge of Lake Michigan, churning out lights for the auto industry.

But now, the company’s management is reluctantly mulling the possibility of moving its production to Mexico to escape the tariffs that President Trump has put on imported components, his primary weapons in a trade war waged in the name of bringing jobs home to America.

“It’s killing us,” said the chairman of the company, Pat LeBlanc, 63, a Republican who voted for Mr. Trump. He now expects the president’s tariffs will chop his 2019 profits in half. “I just feel so betrayed. If we fail because the company is being harmed by the government, that just makes me sick.”