It went worse than had been expected, and expectations were already low. As the supreme court prepared to hear oral arguments in Dobbs v Jackson Women’s Health Organization, a lawsuit over a 15-week abortion ban in Mississippi that constitutes the most serious challenge to Roe v Wade in a generation, many court watchers predicted a massive rollback of abortion rights. But the line among reasonable pundits was that the court, fearing censure from a largely pro-choice American public, would attempt to have its cake and eat it too – allowing states to impose abortion bans earlier in pregnancy, but keeping abortion as a constitutional right intact.

The most convincing version of this argument came from Slate’s Mark Joseph Stern, who predicted that the court, like it did in 1992’s Planned Parenthood v Casey, might weaken the abortion right without abandoning it entirely. In Casey, the supreme court lessened the standard of scrutiny applied to state abortion restrictions – from a robust “strict scrutiny” standard to a more malleable “undue burden” standard – and affirmed that states could ban abortions outright after fetal viability, the point of gestation at which a fetus can survive outside the womb, usually at about 24 weeks.

Stern, like many others, predicted that the court might impose an even more deferential legal test on abortion restrictions – “rational basis review” – and eliminate the viability standard. The result would be that states could ban and restrict abortions more easily, even before viability, but they would still not be allowed to ban abortions entirely. “The court could move back the point at which states can prohibit abortion outright from 24 weeks to 15 or perhaps 12, the end of the first trimester,” Stern wrote. “A diminished right to abortion would survive, battered but extant.”

And yet the end of the viability standard would still have been practically disastrous for abortion access on the ground, as well as for women’s freedom and dignity. This much was elegantly explained by New York’s Irin Carmon, who wrote that attacks from conservatives over the past 30 years have increased the abortion right’s legal reliance on the viability standard, even as developments in pre- and neo-natal care have pushed viability itself earlier in pregnancy. “If a ban on abortion at 15 weeks is allowed for whatever reason, why not draw the line at six?” Carmon asked.

Getting rid of the viability standard, but still leaving the right to abortion technically intact, would in practice invite an anarchic scramble, as conservative states rushed to ban abortion as early as possible and push the limit back sooner and sooner in pregnancy. Julie Rickelman, a longtime abortion rights advocate and the lawyer representing Mississippi’s lone abortion clinic in the Dobbs case, put it bluntly: if viability goes, Roe is effectively no longer good law. “If the court upholds this law, it will be discarding the viability line and overruling Roe,” she told Carmon. “That is the key line in the law that has protected people’s access to abortion.”

In other words, the best-case scenario was legal chaos, misogynist lawmaking, a diminished right to bodily autonomy for women, and millions more people subject to forced pregnancy.

But even these predictions – which pass for “optimism” among legal observers now that the supreme court is held in the chokehold of a conservative supermajority – proved too rosy. At oral arguments in Dobbs on Wednesday, five of the court’s six conservatives showed little interest in maintaining Roe while getting rid of viability. Instead, they were focused on eliminating Roe, and the abortion right, entirely. By the end, it seemed likely that conservatives have a crucial five votes to rule that the constitution does not protect the right to end a pregnancy: Samuel Alito, Clarence Thomas, Neil Gorsuch, Brett Kavanaugh and Amy Coney Barrett.

The lone exception among the conservatives was Chief Justice John Roberts, who seemed almost desperate to direct attention to the viability line. Over the course of arguments, Roberts repeatedly returned to the viability question, emphasizing that it was rejected as a possible standard in the initial 1973 Roe decision and only adopted later, in Casey. But none of the other conservatives took the bait.

The two “swing” votes – if such an extremely and committedly conservative court can be said to have such a thing – are Amy Coney Barrett and Brett Kavanaugh. In a display of the impotence that has marked his career as chief justice, Roberts was unable to persuade either of them to take up his apparently preferred proposition of maintaining a shell of Roe while gutting the viability standard.

Instead, Kavanaugh spent much of his speaking time assuring his colleagues that they need not be bound by Roe’s precedent, listing a long litany of cases in which the supreme court reversed its own prior decisions. Barrett, meanwhile, emphasized the availability of adoption as a supposedly adequate alternative to abortion, at one point asserting that so-called “safe haven” laws, which allow birth mothers to surrender their parental rights and leave their infants in the care of others without punishment immediately after they give birth, offer an adequate remedy for pregnant women who cannot or do not wish to become parents. The idea was that if a woman is pregnant and does not want to be, an acceptable outcome would be for her to gestate and birth a child, and then simply give it away.

The hardest-line conservatives, meanwhile, offered even more grim and ominous assessments of abortion as a matter of law, and their sadistic and extremist views give some indication of where the court may be heading in future cases. Both Alito and Thomas referred repeatedly to abortion as “taking a life”, and indicated that they would be open to recognizing fetal personhood. Until now, post-viability abortion bans have rested on the legal idea that the state has an interest in protecting fetal life that overrides a woman’s interest in controlling her own body after that point. But Alito and Thomas suggested that they think that interest belongs not only to the state, but to the fetus itself, and that this interest begins very early. “The fetus has an interest in having a life,” Alito said at one point. “That doesn’t change from the point before viability and after viability.”

The suggestion that a fetus might have interests in its own right – interests that can be seen as equal or greater than the interests of the woman carrying it – is a dramatic step in anti-choice jurisprudence, one with dramatic implications for women’s healthcare, freedoms, and access to public life. After Wednesday’s oral arguments, it seems certain that Roe v Wade will soon be overturned. For this court, that’s just the beginning.

• Moira Donegan is a Guardian US columnist