Here are six take-home points from Thursday’s supreme court ruling that saved subsidies in the president’s signature healthcare law:

1. What the ruling said

By a 6-3 decision, the supreme court protected subsidies for about 6 million people who have bought health insurance in the last two years under the Patient Protection and Affordable Care Act.

The court rejected a challenge saying the law did not allow for subsidies for patients who purchased insurance in 30 states where the federal government operates insurance exchanges. Subsidies were only meant for state-run exchanges, the challenge said.

The court disagreed.

“Congress passed the Affordable Care Act to improve health insurance markets, not to destroy them,” wrote chief justice John Roberts for the majority. “If at all possible, we must interpret the act in a way that is consistent with the former, and avoids the latter.”

Justice Antonin Scalia contributed an acid dissent. “We really should start calling this law Scotus-care,” he said, referring to a previous, 2012 rejection by the court of a challenge to the law.

2. What the ruling means for patients and insurers

The government says 87% of the more than 7 million people in 30 states who bought insurance through federal exchanges receive subsidies. That’s more than 6 million people. The ruling announced on Thursday means the subsidies will stay in place, removing a threat to coverage for those patients.

The ruling also removes a major source of market insecurity for insurers. Health stocks were up on the news – UnitedHealth Group was up 3% at midday and Humana was up almost 9%.

“If the partisan challenge to this law had succeeded, millions of Americans would have had thousands of dollars’ worth of tax credits taken from them,” President Barack Obama said at the White House on Thursday in a statement welcoming the supreme court decision.

“For many, insurance would have become unaffordable again. Many would have become uninsured again. Ultimately, everyone’s premiums could have gone up. America would have gone backwards.”

3. What the ruling means for the supreme court

The Roberts court has not materialized as the avatar of astringent conservatism some extremely informed observers on the left once fretted it would become. Thursday’s ruling also means that Roberts, a George W Bush appointee, takes on a new role in pop political culture as secret best friends with Barack Obama – and thus a villain on the right.

“Has supreme court justice John Roberts been blackmailed or intimidated?” wondered one far-right site.

Roberts has now beaten back a challenge to the healthcare law not once but twice. In 2012, the chief justice cast the deciding vote in a 5-4 ruling that upheld penalties for people who did not acquire insurance. Critics thought Robert’s reasoning, which judged the penalties to be a kind of tax, exhibited a suspicious elasticity. Roberts wrote that the court should avoid reversing Congress where plausible.

4. What the ruling means for Barack Obama

“The Affordable Care Act is here to stay,” the president said. The healthcare law, if it endures, is a potentially durable stool leg on which an Obama presidential legacy might rest. (If the administration signs a Pacific trade deal, that might make another leg – while the economic recovery or an Iran nuclear deal might make for others.)

The president has 18 months to go, the long-term consequences of the healthcare law won’t be clear for years, and anything can happen. But national healthcare reform is policymaking on a potentially historic scale.

5. What the ruling means for Republicans

The ruling represents a defeat of one of the most closely held and vehemently repeated policy priorities for Republicans since the first Obama term. It’s a setback. On the other hand, Republicans have been freed from having to cobble together their own alternative to the healthcare law. They may now revert to gleefully unaccountable criticism – should they be so inclined.

As for the 2016 presidential contest, the ruling frees certain Republican candidates from a potentially awkward situation in which tens of thousands of people in their home states lose insurance coverage, creating a crisis that could undermine the candidate. Wisconsin governor Scott Walker, for example, should he run, now won’t have to explain why people he kicked off Medicaid weren’t caught by the safety net of federal subsidies, as he said they would be.

6. How Republicans could still defeat Obamacare

“We will continue our efforts to repeal the law and replace it with patient-centered solutions that meet the needs of seniors, small-business owners and middle-class families,” the House speaker, John Boehner, said on Thursday.

Republicans have talked about a plan to repeal provisions of Obamacare as part of a budget bill that they could pass in the Senate with a simple majority and send to the president’s desk. The two fatal flaws in the plan are:

• 1) Such a deal would require agreement between Republicans in the House and Senate on other budget issues they will be hard-pressed to reach agreement on, starting with defense spending.
• 2) Obama would surely veto the bill, which would then die.

Alternatively, Republicans could nominate a winning presidential candidate, hold their congressional majorities and pass a law that carves up the Affordable Care Act. But in a few years, their resolve to do so may have waned.

Or it may have strengthened – and they may have more Democrats on their side. Tracking polls show Americans still view the law unfavorably, with an average of 48% opposing it and 43% in favor.