Has the centerpiece of President Obama’s climate agenda been kicked out? On Tuesday, the Supreme Court ordered a stay of the Clean Power Plan, the landmark regulation intended to cut greenhouse-gas emissions from power plants. The plan is a key element of the pledge the United States made during climate negotiations in Paris last year to lower emissions by 26 percent below 2005 levels by 2025. But now implementation will be on hold until the case against the regulation—brought by conservative states and industry groups—winds its way through the courts.

Here’s the bad news: Although the justices did not explain their order, the 5-4 decision indicates that the majority think the challengers have a chance of winning their case, and that letting implementation move forward during the legal battle will cause irreparable harm to the states and utility companies that are resisting the transition from coal to cleaner sources of energy. The plan, which aims for an overall emissions reduction of 32 percent from 2005 levels by 2030, gives states flexibility on how they go about making cuts, and sets out a three and seven year timeline for developing individualized plans and implementing them, respectively. But the challengers claimed the rule “runs roughshod over States’ sovereign rights,” and that even though the deadlines are years off, they’d have to begin making changes to their infrastructure.

What’s remarkable about the stay is that the Supreme Court chose to step in even before lower courts had a chance to review the case. “Granting a stay in these circumstances is extraordinary,” a White House official told reporters on Tuesday. Just a few weeks ago a federal appeals court refused to block the plan, a move that was interpreted as a victory for the Obama administration. That court will hear oral arguments in early June, though it’s likely the Supreme Court will decide the fate of the plan. Until it does, states won’t be required to comply.

The better news is that it’s really too early to say how the stay will affect the Clean Power Plan. The Supreme Court may uphold the law, ultimately; it’s affirmed the Environmental Protection Agency’s authority to regulate greenhouse gases under the Clean Air Act in several cases since Massachusetts v. EPA set the precedent in 2007. And while the temporary hold may alter the timeline—states were supposed to file blueprints for reducing their emissions in September, and there’s little chance the litigation will be over by then—the actual emissions cuts aren’t due to begin until 2020, and so the delay won’t necessarily cripple it. The White House said in a statement that it is confident in the plan’s “legal and technical foundation,” and that the EPA will “work with states that choose to continue plan development and will prepare the tools the states need” while litigation continues. 

For the coal industry, which responded to the court order with glee, the stay is only a symbolic reprieve. The Clean Power Plan is needed to transform the electricity sector quickly, in order to respond to the rapidly encroaching threat of climate change, and to encourage other countries to stick to their own emissions-reduction pledges. But it’s not the necessary element driving Big Coal to collapse—that’s due to a complex set of economic factors, of which the threat of future regulation is only a part. “The electricity sector has embarked on an unstoppable shift from its high-pollution, dirty-fueled past to a safer, cleaner-powered future, and the stay cannot reverse that trend,” David Doniger of the Natural Resources Defense Council said in a statement.

After the Supreme Court, it’s the next president who will determine the success or failure of the Clean Power Plan. If the rule is fully upheld, whoever is in the White House could choose to enforce it aggressively, or to undermine it. If it falls in the Court, the next administration could find other ways to use the Clean Air Act to regulate carbon-dioxide emissions. Or, the justices could strike down just part of the law, leaving the White House the decision to move forward or scrap the plan altogether. Needless to say, a number of candidates would be delighted to begin their tenure in the White House dancing on the grave of Obama’s signature climate achievement.