The U.S. Supreme Court’s five conservative justices last week went out of their way to throw a roadblock in front of the Obama administration’s Clean Power Plan.

In an unprecedented move, the majority bloc voted to halt new Environmental Protection Agency regulations on power plant emissions from going into effect until a lower court decides on a challenge to the rules. The court historically had deferred to the executive branch’s authority until rules went in effect.

This time, the justices’ ruling suggests that they can’t wait until the case arrives on their docket. They granted a stay requested by 29 state attorneys general and dozens of utilities and energy companies who see the Clean Power Plan as a threat. Whatever side loses in the lower court and appeals to the Supreme Court, it’s pretty clear which way the majority is leaning.

The 29 attorneys general — including Missouri’s Chris Koster — and the other plaintiffs are right: The Clean Power Plan does threaten the status quo. For coal companies, it could be an existential threat.

This isn’t because there’s a “war on coal,” and it isn’t because the Obama administration hates private enterprise. It’s simply because coal-fired plants are responsible for nearly 25 percent of the carbon pumped into the atmosphere by the United States. And atmospheric carbon is warming the planet at a rate that could threaten life on earth by the end of the century.

If this were a giant asteroid headed for earth, as in a disaster movie, the threat would be immediate. There’d be no debate about sending Bruce Willis into action.

The threat from climate change is real, but because it’s happening in slow motion, the sense of urgency dissipates. States like Missouri that depend heavily on coal for energy generation, and states like Kentucky and West Virginia where coal mining is a vital industry, understandably are loath to change.

But change must come. The Clean Power Plan doesn’t take full effect until 2030. It requires states to adapt — but at a pace that minimizes disruption.

For example, Ameren Missouri, whose coal plants accounted for 77 percent of the electricity it generated in 2013, already has begun switching to renewable sources. It could offset the coal it continues to burn with credits for energy conservation programs. According to a Natural Resources Defense Council analysis, enough conservation could enable the utility to phase out its older and dirtier coal-burning plants while meeting its requirement to reduce carbon emissions. That would allow Ameren to avoid the expense of new natural-gas-fired generating plants, thus benefiting shareholders, ratepayers and the planet alike.

The opponents of the Clean Power Plan complain that the EPA went too far into powers constitutionally reserved to the states. The court must decide whether states’ rights trump the future of the planet. In our book, the planet wins the argument.