Yet, coal miners also should not assume their jobs will return if Trump’s regulations take effect.

The new order would mean that older coal plants that had been marked for closings would probably stay open, said Robert W. Godby, an energy economist at the University of Wyoming. That would extend the market demand for coal for up to a decade.

But even so, “the mines that are staying open are using more mechanization,” he said. “They’re not hiring people.”

“So even if we saw an increase in coal production, we could see a decrease in coal jobs,” he said.

Legal experts say it could take years for the Trump administration to unwind the Clean Power Plan, which itself has not yet been carried out because it has been temporarily frozen by a Supreme Court order. Those regulations sought to cut planet-warming carbon dioxide pollution from coal-fired power plants. If enacted, they would have shut down hundreds of those plants, frozen construction of future plants and replaced them with wind and solar farms.