The United Auto Workers union, and many of its members, have publicly agreed with President Donald Trump’s decision to slap 25% tariffs on all imported cars.

But about 900 UAW members will start paying the price for those tariffs starting Monday.

That’s how many hourly workers at five US Stellantis plants will be laid off for two or three weeks because their jobs producing powertrains and stampings for plants in Canada and Mexico have been temporarily idled due to the tariffs.

The layoffs could be a sign of things to come. Since the North American Free Trade Agreement (NAFTA) went into effect 31 years ago, the auto industry has operated as if the US borders with Canada and Mexico did not exist. Components moved freely and frequently between the three countries as they assembled cars, as automakers built millions of vehicles destined for US dealerships at Mexican and Canadian plants.

But those assembly plants north and south of the border were often supplied by American factories. Shutting production at those plants will mean the plants that produce those parts are also at risk.

Three of the Stellantis plants starting layoffs are in Kokomo, Indiana, an island of auto factories amidst a sea of farm fields in the northern part of the state ...

Union members there, even if they agree with the idea of tariffs and their union support of the Trump administration’s policies, are nervous about what the future will bring, said Denny Butler, vice president of one of the three union locals in town.

Butler said he and other autoworkers are very nervous about what happens to jobs in Kokomo as a result, not just from this current round of layoffs but in future months and years. There were already 400 UAW members on indefinite furlough in Kokomo even before Monday’s layoffs ...

He agrees that NAFTA hurt autoworkers by encouraging automakers to build plants in Mexico to take advantage of low wages there. The union’s parking lot contains a warning sign that non-union cars, such as those built in Mexico, will be towed.

But he said he didn’t believe the plants will quickly return just because tariffs are in place.

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