The announced plant shutdowns of the U.S. carmaker are a hard blow to Trump’s economic policy.

The announced job cuts at carmaker General Motors cut U.S. President Donald Trump to the quick. In Trump’s strongholds in Ohio and Michigan, of all places, the lights are set to go out in several plants because costs are skyrocketing. Trump alone is to blame for the rising expenditures because since the spring, carmakers have had to pay import charges of 10 percent on aluminum and 25 percent on steel.

The special steel that is used in modern vehicles cannot be quickly produced in the American market. Various steel works which have recently ramped up production are focusing on quantity rather than quality.

GM is undoubtedly facing a fundamental reorientation. Increasingly, electric cars and self-driving vehicles are set to take the place of large limousines and pickup trucks. All of the reforms are difficult, given the explosion in costs for materials.

We can only hope that Trump and his economic advisor Robert Lighthizer do not forget the warnings from domestic carmakers the next time they talk to the Europeans about trade-related matters.