On Thursday the Supreme Court made its second significant ruling on President Barack Obama’s healthcare law, finding in a 6-3 decision that federal subsidies offered through the Affordable Care Act should be available to all subscribers, regardless of whether the states in which they live have set up their own health insurance marketplaces.

The question the court had to consider was whether Americans that receive their insurance through a federal-run health insurance marketplace, as is the case in 34 states, should be eligible for federal subsidies that help make that health insurance affordable.

Opponents to the law argued the subsidies should only be available to those whose states operate their own health insurance marketplaces.

In the majority opinion, Chief Justice John Roberts wrote, “Congress passed the Affordable Care Act to improve health insurance markets, not to destroy them.” In a press conference, Obama declared the law is “here to stay.”

Here, Wendy Parmet, an expert in health policy and law who has joint appointments in the School of Law and the School of Public Policy and Urban Development, discusses the court’s decision and the future of the healthcare law.

What does this ruling mean for Americans and what is its significance for the healthcare law?

Most directly, the court’s decision means that the more than 6 million Americans who receive their health insurance on federally-established exchanges can continue to be insured and get the healthcare they need.

More indirectly, it ensures that health insurance will remain in place for millions of other Americans who rely on the ACA, as a ruling against the Obama administration might well have begun the process of dismantling the law. Given the court’s ruling, and the decisive manner in which it reached that conclusion, there is good reason to believe that the fights over the very existence of the law will begin to dissipate.

What significance can be drawn from the 6-3 vote and the choices of the justices—Chief Justice John Roberts and Associate Justice Anton Scalia—who wrote the majority opinion and dissent, respectively?

The 6-3 vote shows that there was a strong majority on the court willing to support the Obama administration’s position. Perhaps even more remarkable is that all six members of the majority joined Chief Justice Roberts’ opinion. He was able to put together a majority that spoke with one voice, suggesting his increasing influence over the court. This unanimity among the majority will make it harder for those who wish to challenge the ACA to find potential cracks on the bench.

As for the dissent, it isn’t at all surprising that Justice Scalia authored it, or that he was joined by Justices Thomas and Alito. They are the most conservative members of the court, and all of them voted to strike down the ACA in 2012. In addition, Justice Scalia has long been opposed to the mode of statutory construction that Chief Justice Roberts used today. A staunch advocate of the so-called plain meaning rule, Justice Scalia has frequently condemned reading a statute in context.

Is the healthcare law here to stay, or will it continue to be challenged by politicians and lawmakers?

Without question, many Republicans will continue to call for the repeal of the ACA. But with the court now upholding the ACA for a second time in three years, and with more and more Americans relying on and becoming used to accessible and affordable insurance, it appears as if the ACA is here to stay.

The longer it is in place, the harder it will be for politicians to repeal and take away the insurance that Americans have come to rely upon. That doesn’t mean that changes won’t be made. But a repeal is going to be politically costly.