If there was one thing of which I was certain going into this week’s Supreme Court hearings, it was that, at worst, the justices would strike down the individual mandate and related coverage positions. In other words, they’d get rid of requirements that insurers cover everybody at a uniform price, on the theory those reforms don’t work without the mandate. But the other major pieces of the law – the expansion of Medicaid to cover 15 million people, the changes to the way Medicare pays hospitals, and so on – would stay.

After this morning’s oral arguments, I am not certain of that anymore.

I’m not saying a wholesale invalidation is probable. In fact, I’m not even saying invalidation of the mandate is probable. I really don’t want to hazard guesses or predictions about what the justices will decide.

But the conservative judges asked questions suggesting they were at least contemplating throwing out other portions of the law – and maybe the whole thing – if they rule against the mandate. And, yes, that included Justice Anthony Kennedy, on whose vote the mandate itself appears now to depend.

Afternoon arguments begin shortly, so I don’t have time to write much. And this is a complicated session to explain, because three different lawyers made three different cases. Paul Clement, representing the states, argued that the entire law should go. Edwin Kneedler, Deputy Solicitor General, argued that only the two coverage reforms – known as “guaranteed issue” and “community rating” – should go, although the government also maintains the Court should not address that issue yet. H. Bartow Farr, an attorney selected by the court, argued that the rest of the act should stand even if the Court decides to invalidate the mandate.

The justices asked tough questions of both Clement and Kneedler – in that sense, it felt a bit more even than yesterday. But a familiar ideological divide eventually emerged.

One by one, the liberal judges went after Clement, wondering why other portions of the law that benefitted people should go just because the mandate does.

“Half a loaf is better than no loaf,” Justice Elena Kagan said, while Justice Ruth Bader Ginsburg suggested the Court had the “a choice between a wrecking operation or a salvage operation. The more conservative approach is the salvage operation.” (Note: These quotes are from the notes I took, so may not be entirely verbatim.)

Once Kneedler began presenting, the conservative judges began their assault, wondering about how removal of the mandate could ripple through the rest of the law. It might inflate the deficit, they noted, or cause problems for insurance companies.

The impact on people who can’t get health insurance right now – like, for example, the 15 million people who would lose coverage if the Court also throws out the Medicaid expansion – did not seem to be a subject that weighed heavily on their minds.

Among those asking the questions was Kennedy: “We would be exercising judicial power to impose a risk on insurance companies that … was never intended. That can be argued to be a more extreme exercise of judicial power.”

Justice Samuel Alito offered some budget figures, as he did yesterday, suggesting that removing the mandate would saddle the federal government with a massive budget hole. Justice Antonin Scalia made the same point at another instance.

Of all the justices, Sonia Sotomayor seemed to display the best understanding of the actual health care law, by noting that states have used other reforms, besides the mandate, to help stabilize the insurance market even in the absence of a mandate. This was Farr’s essential point: That the mandate was a tool for making the coverage provisions work – an important tool, for sure, but not the only one. (I happen to think this is right – see my post from late last night.)

What this all means, I can’t really say. As was the case yesterday, the signals from Kennedy along with Roberts and to a lesser extent Alito were difficult to read. And first impressions from oral argument can be very, very wrong. No outcome would surprise me at this point, and that includes everything from upholding the whole law to striking the whole thing down.

But it’s a little breathtaking to contemplate that the five robed men I’ve been watching these past three days have the power to deprive 30 million people of health insurance, tens of millions more of insurance security, and undo a reengineering of health care that’s already underway.

It’s still hard for me to imagine they’d actually do it. But not as hard as it was a few hours ago.