It has been a bad month for the fight against climate change. Amid heat waves, wildfires, droughts and Arctic ice melt, President Trump has taken aim at the two central pillars of his predecessor’s ambitious efforts to reduce carbon dioxide emissions. After proposing in early August to freeze a scheduled increase in fuel economy standards for cars and light trucks, the Trump administration on Tuesday said it would seek to significantly weaken the Obama-era Clean Power Plan, aimed at reducing greenhouse gas emissions from coal-fired power plants.

Those two economic sectors — transportation and electricity production — are the biggest contributors to greenhouse gas emissions in the United States, accounting for 56 percent of the total.

In taking on the Clean Power Plan, Mr. Trump says he wants to save coal, but the reality is that coal is not coming back. Market forces conspire against it. Even without any policy, the economic imperatives driving the transition to cleaner fuels are expected by 2030 to reduce carbon dioxide emissions in the power sector by 33 percent of their 2005 levels, according to the Environmental Protection Agency. With the Obama plan, the reduction would be 36 percent; with the Trump administration’s new Affordable Clean Energy Rule, it would be 33 to 34 percent.

Coal’s decline is being driven far less by government regulation than by cheap natural gas prices and the falling costs of renewable energy. Therefore, scrapping President Barack Obama’s Clean Power Plan can’t save coal — although the Trump administration’s misguided plan to subsidize uncompetitive coal plants could, at least in the short term .