Abortion supporters gather outside the Supreme Court, in Washington, on November 1, 2021.

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CNN  — 

This could be the moment when some combination of Republican-appointed Supreme Court justices agrees to break 50 years of precedent by removing the national right to an abortion recognized in Roe v. Wade.

The court has a hearing over a Mississippi abortion law Wednesday, and the 6-3 conservative majority seems primed for action.

A separate, notorious Texas abortion law is also before the court. But it is the Mississippi case that is a direct challenge to the landmark Roe v. Wade decision, which established a woman’s constitutional right to end a pregnancy.

Many states have been so intent and creative on chipping away at the precedent that even a half-measure by the court could create a post-Roe reality. For women who live in states with few abortion providers and numerous hurdles to gain access, it may feel like a post-Roe reality right now.

But either by overturning Roe or scaling it back, the court could, when it hands down a decision next year, make it much easier for states to ban or more seriously restrict abortion rights.

What does Roe guarantee? The 1973 decision said states can’t ban abortion unless a fetus is viable, or can survive outside the womb. The Supreme Court ruled that a woman’s right to an abortion was covered by the right to privacy under the 14th Amendment of the Constitution.

When the case was decided, that viability standard was 28 weeks, but it’s now considered to be from 22 to 24 weeks of gestation.

Must read: This story from CNN’s Joan Biskupic about how the 1973 court settled on that standard at the last minute. Back then, she points out, it was Republican-appointed justices concerned with privacy rights who helped set the precedent.

Question: What’s the difference between a woman’s right to privacy over pregnancy, which Republicans today want to disregard, and the right to privacy over, say, Covid-19 vaccinations, which they want to protect? We’ll save that for another newsletter.

What would the Mississippi law do? It’s a direct challenge to Roe v. Wade since it would ban abortions after 15 weeks of gestation, well before the current viability standard. Abortions after 15 weeks of pregnancy would be allowed “only in medical emergencies or for severe fetal abnormality.” There is no exception for rape or incest.

Even something less than a full Roe reversal could change laws in much of the country.

Roe has been law for nearly 50 years. Will that matter? CNN’s Ariane de Vogue writes that if the court overturns Roe, it could go “to the stability of the court as an institution.”

She writes: “Put another way: if the court uses cases as building blocks to construct the rule of law, what happens when one block – put in place in 1973 – is yanked out?”

I’ll take that a step farther, even though I’m not a constitutional lawyer. Today I read the 14th Amendment to review what it says about privacy. That concept that’s so key to Roe, it turns out, is not spelled out with the word “privacy” in the 14th Amendment. The protection of privacy has been built by the court over decades, and Roe is a key part of that structure.

Political backlash is guaranteed. Perhaps more predictable is the political backlash to a Supreme Court controlled by Republican appointees removing a right for women.

I think if you want to see a revolution, go ahead, outlaw Roe v. Wade and see what the response is,” said Sen. Jeanne Shaheen, a Democrat from New Hampshire, on Monday. She compared state control of women’s reproductive health to “something we would see in an authoritarian state” during an appearance on the New Hampshire station WMUR.

Abortion would suddenly become a key issue at the state level, too. In Virginia, for instance, the governor-elect, Glenn Youngkin, a Republican, has tried to de-emphasize the issue of abortion, to the consternation of anti-abortion-rights activists who supported his campaign.

The majority of Americans support upholding Roe v. Wade. Numerous polls have confirmed this general public support for abortion rights. For example, an ABC News/Washington Post poll from November found 60% of Americans said the Roe precedent should remain, compared with 27% who supported overturning it.

There is, however, variation in public support for abortion rights depending on the details of the situation. Although there is a long history of broad support for maintaining Roe, the share in support of legal abortion without any sort of government restriction is far smaller, according to Gallup polling going back decades.

Where would abortion be illegal? Twenty-six states are certain or likely to ban abortion procedures if Roe is overturned, according to the Guttmacher Institute, which supports abortion rights. This includes states that would institute total bans on abortion, bans at 15 weeks of pregnancy and bans at 20 weeks. A dozen states have laws on the books to automatically ban abortions if Roe is overturned.

The institute issued a report suggesting that Americans in the half of the country with abortion bans could drive hundreds of miles to access abortions if Roe is overturned, and guessed there could be a rush of demand in states where abortion remained legal, particularly Illinois and North Carolina.

Could a national abortion standard be set? Sure, Congress technically has the ability to write a national abortion standard. That might not be a political reality, since a minority in the Senate can block most major legislation.

More women talking about abortion. Many Americans either weren’t alive or can’t remember 1973. That includes the women who in recent months and years have shared stories of how and why they got abortions.

Three members of Congress shared their stories at a hearing in September.

“To all the Black women and girls who have had abortions or will have abortions, we have nothing to be ashamed of,” said Rep. Cori Bush, a Missouri Democrat. “We live in a society that has failed to legislate love and justice for us. So we deserve better. We demand better. We are worthy of better.”

“So that’s why I’m here to tell my story,” she said.

On “Saturday Night Live” in early November, the comedian Cecily Strong wore a clown costume to open a dialogue on abortion.

“I wish I didn’t have to do this, because the abortion I had at 23 is my personal clown business,” Strong said.

CNN reported at the time: “In her new memoir ‘This Will All Be Over Soon,’ Strong is not explicit on whether she had an abortion but she does say that she was pregnant at 23 and soon after was ‘not pregnant anymore.’ “

For about half the country, that’s a choice women may soon not be able to make in their home states.