Open enrollment ended on Saturday, but Obamacare did not. Photo: Joe Raedle/Getty Images

Last night’s sudden and strangely timed decision from a federal judge in Texas striking down the entire Affordable Care Act seemed to take everyone, even the Trump administration and 20 Republican attorneys general and governors who brought the suit, by surprise. Though U.S. District Judge Reed O’Connor has yet to issue a final ruling, and the government has announced that the ACA will be enforced during the inevitable appeals process, the sheer scope of the decision has taken many breaths away. Its foundation was the claim that Congress’ repeal (in last year’s big tax bill) of the tax penalty underlying the individual mandate made the mandate unconstitutional, given the Supreme Court’s reliance on the federal government’s taxing power in ruling the law was constitutional in 2012. O’Connor might have simply decreed the mandate dead. But as Axios notes, he threw out the baby with the bath water:

This was an amazingly broad ruling. The judge didn’t just strike down everything that’s related to the individual mandate. He struck down everything, period. That includes the parts that everyone likes, like the expansion of Medicaid, young adults staying on their parents’ plans — and, of course, coverage of pre-existing conditions.

This creates not just a fear factor for people who rely on various provisions of the Act and the Obamacare program that it created, but also a major political challenge for the Republican dogs who have finally caught the bus of Obamacare repeal, albeit via a judge whose decision could easily be overturned. Democrats had already used the latest lawsuit to accuse Republicans (especially the attorneys general involved) of wanting to get rid of insurance coverage for people with preexisting conditions. Now it could be a reality, at least until the appeal process plays out, as the Washington Post notes:

The big question facing Republicans is whether they will support legislation that protects people with preexisting conditions. Throughout the campaign, Democrats pointed out what they called the hypocrisy of Republicans supporting the lawsuit while also telling voters such protections would be preserved. The problem with that promise is that Congress has not put in place any safeguards or contingencies for those protections in the event the law gets overturned.

That’s the most politically pressing but not the only problem O’Connor’s decision poses for Republicans. The ACA also provided authority for a number of Trump administration health care initiatives, and for some alternative GOP approaches to unpopular Obamacare provisions. And the 19 Republican-governed states that heavily rely on an expanded Medicaid program will be as panic-stricken as their Democratic counterparts if the ACA actually goes down.

The odds of that happening aren’t high according to many legal experts, even those who sympathize with O’Conner’s antipathy to the individual mandate. Most figured the principle of severability would save the ACA even if the mandate fell, the New York Times notes:

[E]ven though Congress erased the tax penalty, it did not touch the rest of the sprawling health act. A longstanding legal doctrine called “severability” holds that when a court excises one provision of a statute, it should leave the rest of the law in place unless Congress explicitly stated that the statute could not survive without that provision. In this case Congress’s intention was particularly clear, legal experts said.

“Congress amended one provision of a 2,000 page law and did not touch the rest of the law so it is implausible to believe that Congress intended the rest of the law not to exist,” said Abbe R. Gluck, a health law expert at Yale Law School.

What happens next is not entirely clear, as two legal scholars reacting to the decision in a Times op-ed explain:

The health law is likely to continue in place while the case moves to the higher courts. California, the leader of a group of states that stepped in to defend the law because the Justice Department refused to do so, will almost certainly go to the Fifth Circuit — the federal appellate court that presides over Texas — to have the effects of the decision paused and the case reviewed. The House of Representatives will also likely join the lawsuit once the Democrats take control.

If the Fifth Circuit reverses Judge O’Connor, we think it unlikely the Supreme Court will take the case. If the Fifth Circuit upholds the ruling, we are skeptical a majority of the court would sustain this weak analysis.

But even if O’Connor’s decision turns out to be a footnote of legal history, the uncertainty could afflict millions of Americans and roil the political system. Republicans may feel obliged by their long history of Obamacare-hating to celebrate the decision, as their president did:

As I predicted all along, Obamacare has been struck down as an UNCONSTITUTIONAL disaster! Now Congress must pass a STRONG law that provides GREAT healthcare and protects pre-existing conditions. Mitch and Nancy, get it done! — Donald J. Trump (@realDonaldTrump) December 15, 2018

Easy for him to say. Trump has always thought health care was too complicated to discuss in more than vague generalities that others would have to explain. If anyone is explaining this ruling to him now, they should point out that victory, in this specific case, would probably just become another Trump-branded disaster.