The decades-long campaign of resistance to Roe also sets it apart from those rulings. Griswold and Lawrence didn’t lead to any such campaign. Without state legislation to outlaw contraception or sodomy, even a justice who wanted to overturn those rulings would not have any occasion to do it. (This is something Justice Amy Coney Barrett tried to explain during her confirmation hearings.)

Opponents of Roe also had the option to fight it in increments. They could ban some types of late-term abortions, require parental notification or restrict the activities of women’s health clinics, for example, and ask the courts to allow those laws. Eventually, they built up to bans on abortion after 15 weeks of gestational age, the restriction specified by the 2018 Mississippi law that has put the issue before the Supreme Court now. These laws are popular in most polls, gaining support even from some people who consider themselves pro-choice, but directly conflict with Roe. As both parties arguing the Mississippi case agreed, the justices had to choose between keeping the law and keeping Roe.

Same-sex marriage is, by contrast, a binary choice; there’s no equivalent strategy for chipping away at the right in legislatures and courts. A state would have to take it on directly, and there’s no fuzziness about the borders of the holding that would enable state laws to make their way up the courts to the justices.