Trump had a good idea how he had flipped it. “During the campaign, I came to Michigan again and again, and I made this promise, that I am going to fight for your jobs,” he said. Now he would make good on that vow. He claimed to have persuaded the “Big Three” American automakers—Ford, General Motors, and Fiat Chrysler—to preserve or create a total of 3,600 auto jobs in the United States. But the country needed to think bigger. “We must embrace a new economic model,” he said. “Let’s call it the ‘American model.’”

With this declaration, Trump began one of the greatest fiascos of his presidency. His initiative would eventually entangle three federal agencies, four automakers, and 13 states. It would devour decades of billable time from legions of corporate lobbyists and lawyers. And it would stymie every person who hoped to buy a new car in the United States from 2021 to 2026—or, for that matter, every person who planned to use an American highway, or breathe American air.

That day at Willow Run, Trump was also about to make a promise that he couldn’t keep.

Trump’s “American model,” as he described it, established a new bargain between American companies and American workers. As part of this deal, the federal government would cut regulations and reduce burdens on U.S. companies. In exchange, those companies had to hire more American workers and buy American products. “That is how we will succeed and grow together—American workers and American industry side by side,” Trump said.

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This vision, depending on the angle, looked like either a proudly nationalist way of doing business or an oddly lopsided agreement. If the companies got their rollbacks but then didn’t hire American workers, what could the government do about it? By cutting regulation first, it had already sacrificed its clout.

But this point went undiscussed, because Trump knew which rule he wanted to clip first: the Corporate Average Fuel Economy standards, or CAFE standards, which governed the gas mileage and tailpipe pollution of new cars, light trucks, and SUVs. “I’m sure you’ve all heard the big news,” he said. “We’re going to work on the CAFE standards so you can make cars in America again.”

The CAFE standards did not actually concern whether cars could be made in America. But since 2012, the rules had required that new vehicles must get about 5 percent more fuel-efficient every year, while simultaneously restricting the amount of heat-trapping carbon pollution they could emit. The rules had, in a word, worked: They had pushed the country’s fleet-wide fuel economy to an all-time high, prevented millions of tons of carbon from blanketing the atmosphere, and saved consumers hundreds of billions of dollars at the pump. They were also one of the most consequential climate-change protections in American history.