It seems obvious enough that for the past few years, it has been suboptimal to have our approach to one of our biggest challenges — the threat to humanity’s future posed by global warming — shaped to no small degree around two of President Trump’s worst pathologies. We’re talking about the bottomless zeal to destroy former President Barack Obama’s legacy and the frequent denial of climate change’s very existence.

But the news that General Motors has abruptly withdrawn its support for the Trump administration’s efforts to revoke California’s legal right to place stringent limits on auto emissions, instead siding with California, crystallizes the point in a new way, one that bodes well for the possibilities of Joe Biden’s presidency.

The news was just delivered by GM itself:

“President-elect Biden recently said, ‘I believe that we can own the 21st century car market again by moving to electric vehicles.’ We at General Motors couldn’t agree more,” Mary Barra, the General Motors chief executive, wrote in a letter Monday to leaders of some of the nation’s largest environmental groups.

Barra’s letter also noted that Biden has pledged to reverse Trump’s approach by taking fast action to reduce vehicular emissions, and added:

“We believe the ambitious electrification goals of the President-elect, California, and General Motors are aligned to address climate change by drastically reducing automobile emissions,” she wrote. “We are confident that the Biden Administration, California, and the U.S. auto industry, which supports 10.3 million jobs, can collaboratively find the pathway that will deliver an all-electric future.”

To understand why this is a big deal, recall that when it comes to curbing auto emissions, the Trump administration sought to destroy a very important achievement on Obama’s part.

Obama’s vehicle standards required automakers to nearly double on average the fuel efficiency of new cars and trucks by 2025. When Trump moved to roll back those standards — as part of a much broader rollback of Obama’s environmental legacy — he was actually moving to wreck a careful balance that had been achieved.

This balance had been struck by getting auto companies to agree to seriously curb emissions over time, putting additional pressure on them to innovate toward electric and more efficient vehicles, in exchange for a measure of certainty that they could build business models around.

Under federal law, California has long enjoyed the latitude to develop its own environmental standards, separate from federal ones. Auto companies had long objected to having to navigate the differences, according to David Doniger, a senior analyst with the Natural Resources Defense Council.

Obama’s achievement aligned those into one set of standards. Doniger has long called this the “Clean Car Peace Treaty,” because “we had been fighting over this stuff for decades,” as he told me, and now it had been resolved.

Trump upended that arrangement. To make matters worse, his administration sought to revoke California’s right to set its own emissions standards, something that is embroiled in a huge legal fight.

Remarkably enough, earlier this year, five auto companies cut a separate deal with California to honor its stricter emissions, rather than lapse back to the higher pollution levels the Trump administration seemed hell-bent on restoring.

This appeared to amount to a bet that Biden might win the presidency and reinstate stricter rules, meaning it would be better for business to establish consistency over the long haul. As Coral Davenport pointed out in the New York Times, in so doing, these companies locked themselves into “selling more fuel-efficient, lower-polluting vehicles” over time, in exchange for having what one of the companies described as “regulatory certainty.”

General Motors was not one of those companies. It previously sided with the Trump administration’s effort to revoke California’s right to set its own standards. And to be clear, now that GM has switched sides, it’s not endorsing stricter rules, it’s just siding with California’s right to set them. It’s also still possible that auto companies will put up a huge fight against Biden’s efforts to reinstate stricter federal standards.

But now that GM has flipped, it nonetheless bodes well. With a president who doesn’t reflexively see climate deregulation as a good in and of itself — one who doesn’t see the problem as a “hoax,” as Trump does — we might see a more sensible mixed-economy approach restored, one that holds the possibility of business and government cooperating toward solving profound societal problems.

Doniger said this could also align the government with the technological and societal evolution that is already happening, rather than pitting the government against these trends for rigid ideological reasons (such as the insistence that climate change isn’t a serious problem).

“The odd thing about all this is that during the Trump years, the push to go from gas engines to electric has just increased,” Doniger told me. “California is going that way. It’s increased in many other countries.”

“Car makers see the technology writing on the wall,” Doniger said. “The Biden campaign integrated climate change and economic recovery. If you want to ‘Build Back Better,’ you build back in a way that moves from old polluting technologies to new ones that fight climate change.”

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Post Senior Producer Kate Woodsome talks to Americans who voted for Trump, or simply don't feel like denouncing him, about why they feel wrongly scorned. (The Washington Post)

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