WASHINGTON -- "I win. Every time." So said Chief Justice John Roberts during Supreme Court argument Wednesday afternoon, stepping into the shoes of some hypothetical head of a federal agency hellbent on making the states do his bidding lest he bring them to their knees.

But he might as well have been speaking for himself and his four fellow Republican-appointed colleagues as they took an ax to the Affordable Care Act this week.

After appearing united on Monday in brushing off a legal technicality they could have used to punt away the politically charged challenge for a few years, the justices split hard on Tuesday over the individual mandate's constitutionality. The chief and Justices Antonin Scalia, Anthony Kennedy and Samuel Alito all hit hard on Solicitor General Donald Verrilli's defense of the health care law's key provision that virtually every American, starting in 2014, must have health insurance or pay a penalty.

Although Kennedy may have softened his hard-line stance near the end of Tuesday's argument, there was nothing moderate about the positions he or the rest of the conservative majority took during Wednesday's doubleheader. Lawyers for the government and the challengers -- 26 states, the National Federation of Independent Business and several individual plaintiffs -- addressed two questions: whether the individual mandate can be severed from the rest of the health care law and whether the expansion of Medicaid violates states' rights.

Paul Clement, appearing on behalf of the challengers, started out the morning telling the justices that if "the individual mandate is unconstitutional, then the rest of the act cannot stand."

Until Wednesday morning, that argument sounded like overkill: The one federal appeals court to strike down the mandate left standing the rest of the law, reversing the one federal trial court that had found the mandate unseverable.

Indeed, Justice Sonia Sotomayor early in Clement's argument suggested that it was Congress' job, not the Supreme Court's, to determine what to do with the rest of the law if the mandate is removed.

Justice Ruth Bader Ginsburg agreed. "It's a choice between a wrecking operation, which is what you are requesting, or a salvage job," she said. "And the more conservative approach would be salvage rather than throwing out everything."

But in Kennedy's world -- which his key swing vote makes our world, too -- severing the mandate would actually be a more "extreme exercise of judicial power" than striking down the entire Affordable Care Act. To leave the remainder of the law standing, he said, would create a "new regime that Congress did not provide for, did not consider."

The Obama Administration took a middle ground, arguing that the law's popular "guarantee issue" and "community rating" provisions cannot survive without the mandate. Guarantee issue bars insurers from discriminating against people with pre-existing conditions, and community rating standardizes insurance premiums for those living in the same area.

Justice Stephen Breyer, trying to restrain his colleagues, listed off some provisions, including one addressing Native American health care and another focused on black lung disease, that have nothing to do with the mandate, guarantee issue or community rating.

But Roberts characterized those provisions as the "price of the vote," essential for Congress to "cobble together the votes to get [the Affordable Care Act] through."

Scalia, for his part, said it would be torture to go line-by-line through the law evaluating each provision. "What happened to the Eighth Amendment? You really want us to go through these 2,700 pages?" he asked.

"My approach would say if you take the heart out of the statute, the statute's gone," Scalia said, putting Kennedy's earlier point more bluntly.

Even on the off chance that Kennedy scared himself away from striking down the mandate with his absolutist stance on severability, he seemed to put himself in the apparent majority to strike down the other provision that goes a long way toward achieving universal health care.

Clement argued on behalf of the states that the Affordable Care Act's Medicaid expansion, which requires states to cover citizens under age 65 whose income falls below 133 percent of the poverty line, forces the states to pay unaffordable costs or lose all Medicaid funding.

The federal government, however, will initially pay all the costs for expanded coverage when it begins in 2014, dropping to a still-generous 90 percent in 10 years' time.

Justice Elena Kagan started the questioning in this final oral argument of the health care cases by noting the apparent absurdity of Clement's position.

"The federal government is here saying we are giving you a boatload of money," Kagan said. "There's no matching funds requirement. There are no extraneous conditions attached to it. It's just a boatload of federal money for you to take and spend on poor people's health care. It doesn't sound coercive to me, I have to tell you."

Yet Kagan's early push made no headway with her conservative colleagues. After spending most of Clement's argument in near-total silence, they unleashed upon the solicitor general a limited view of Congress' spending powers that every lower court that heard a health care law case -- even the ones that struck down the mandate -- had rejected.

With five justices looking hostile to the government's arguments and unswayed by the liberal bloc's appeals to precedent, Verrilli was left to conclude with a plea to their emotions.

The Medicaid expansion, he said, would provide health care to "millions of people with chronic conditions like diabetes and heart disease," letting them be "unshackled from the disabilities that those diseases put on them" and giving them "the opportunity to enjoy the blessings of liberty."

Clement, on rebuttal, called it "a direct threat to our federalism" and snuck in a final blow against the mandate as a "very funny conception of liberty that forces somebody to purchase an insurance policy whether they want it or not."

The chief justice had the last words of the day, thanking all the lawyers and submitting the case for the Supreme Court's ultimate decision by late June.

The marshal then banged her gavel, and as all stood in the courtroom, Breyer swiftly exited behind the curtain, shaking his head, perhaps remembering his words to an open court five years earlier that "it is not often in the law that so few have so quickly changed so much."

The boldly conservative Roberts Court was in its infancy then. This week, it came of age.