The head of the California Air Resources Board, Mary Nichols, came very close this week to saying the state was prepared to ban the internal-combustion engine if necessary to maintain air quality and fight climate change. A line about taking that step even made it into her prepared remarks, but when she delivered the speech Thursday in San Diego, that part was left out. From Bloomberg:

“If we lose the state vehicle standards, we have to fill up the gap with other measures,” Nichols said at a forum on the issue Thursday. “We will be faced with dramatic alternatives in terms of tighter, stricter controls on everything else, including movement of vehicles and potentially looking at things like fees and taxes and bans on certain types of vehicles and products.”

Nichols did not explicitly outline possible changes at Thursday’s event, which was held to discuss the consequences of the Trump proposals and potential California countermeasures. But in remarks prepared for the meeting, she raised the specter of outlawing conventional vehicles with combustion engines, as well as tougher anti-pollution requirements on everything from fuel to the refineries producing it.

“CARB will be exploring ways to ensure communities get the reductions of air pollution they so desperately need to keep the air clean and breathable — and continue to fight climate change,” Nichols said in the drafted remarks, which she did not deliver exactly as prepared. “That might mean, for example, tougher requirements for low-carbon fuels, looking at tighter health-protective regulations on California refineries, doubling down on our enforcement efforts on mobile and stationary sources — and might lead to an outright ban on internal combustion engines.”

Sales of all-electric vehicles are higher in California than in the country as a whole but still only represent about 8 percent of the total market. The idea of banning the other 92% of cars probably would not go over well with people outside San Francisco. Still, it’s revealing that a state bureaucrat came this close to suggesting it was a possibility. Clearly, this is something the California Air Resources Board has thought about even if Nichols was ultimately afraid to say it.

The Trump administration announced plans to roll back Obama administration CAFE standards last year. The White House had been negotiating with the California Air Resources Board until February when those negotiations ended in sharp disagreement:

“Despite the administration’s best efforts to reach a common-sense solution, it is time to acknowledge that CARB [the California Air Resources Board] has failed to put forward a productive alternative,” the White House said in a joint statement with the Environmental Protection Agency and Transportation Department.

However, some California officials said real talks never really began. They said sessions between the heads of the Environmental Protection Agency and CARB were not substantive and never progressed into the nitty-gritty of policy negotiations…

The Obama regulations, which run through 2026, would raise the corporate average fuel economy, or CAFE, standards for new cars and trucks to 36 miles a gallon in what the EPA calls real-world driving. The sticker mileage would rise as high as 54.5 miles a gallon. The Trump administration change would reduce that to 29 miles a gallon in real-world driving, according to Daniel Becker, director of the Safe Climate Campaign.

So it appears a compromise is not likely for now. I very much doubt the state will decide to bang the internal-combustion engine on its own anytime soon, but this is California so you really never know.