BOSTON — If I hear one more person refer to Sandra Day O’Connor as the swing vote on the Supreme Court, I’ll ban him forever from my playground.

I have a different metaphor for the first woman on the Supreme Court or, as she described herself archly, the FWOTSC. She’s the Justice of the Peace, occupying a rather female ground as the mediating force in the court and the country.

For better and sometimes for worse, I have imagined O’Connor sitting at a squabbling family table saying, &uot;I don’t care who started it — Antonin, don’t talk with your mouth full! — I just want peace

and quiet.” Who does that remind you of? Mom?

As several justices said after O’Connor’s retirement announcement, she brought us closer together. But it’s pretty clear now that without mom, the kids are going to behave badly. The divisiveness can be seen already in the groups issuing rallying cries. &uot;The Battle is Joined!” says one side. The other warns: &uot;Everything You’ve Fought For is At Stake.”

The talking heads are discussing the different flavors of conservative jurists — traditional, originalist, pragmatic or libertarian. But the elephant in the room is abortion. This may not be the &uot;Armageddon vacancy” for Roe v. Wade, but it’s awfully close.

O’Connor, appointed after a campaign promise by Ronald Reagan and the only justice on this court who’d ever held elective office, found and kept the center on abortion.

In 1982, O’Connor warned that Roe was on a &uot;collision course with itself.” Then in 1989, a solicitor general for George the First came to court saying, &uot;Today the United States asks this court to reconsider and overrule its decision in Roe v. Wade.” But O’Connor asked: &uot;Do you say there’s no fundamental right to decide whether to have a child or not?” What if, in the future, we had a serious overpopulation problem, she continued. Does the state have a right to require abortions?

She found a way to swerve from the collision course. She kept the peace by upholding Roe while allowing states to regulate abortion as long as they didn’t put an &uot;undue burden&uot; on the basic right to choose.

For a while an undue burden was pretty much whatever this justice said it was. It wasn’t an undue burden to legislate a waiting period or parental consent. It was an undue burden, said the first justice who had ever been pregnant, to ban &uot;partial birth abortions&uot; without a health exception.

At times I disagreed with her. But she expressed the view of the unmuddled middle, that majority of Americans who clearly want abortion to remain legal but restricted. As Frances Kissling of Catholics for a Free Choice says, &uot;Americans believe that abortion should remain a right but that it’s also a morally serious business. They want someway to express that.”

This balance is at stake as the groups gird for war and scan the backgrounds of O’Connor replacements from Attorney General Alberto Gonzales to appellate Judge Michael McConnell.

Nearly two-thirds of the country want Roe v. Wade upheld. More than 30 million American women have had abortions since Roe was decided. Even the president tiptoes politically around Roe, talking about &uot;changing hearts&uot; before laws. How did it get to the point where the right to abortion is hanging by one or two votes … in the Supreme Court?

We know the two shaky ends of the argument. The leadership of the anti-abortion right has successfully marketed &uot;pro-life” as &uot;pro-children and pro family.&uot; But they never come to grips with how deeply the government should intrude in private life.

On the other hand, the pro-choice leaders, on the defense, have not spoken as carefully to the majority. Asks Kissling: &uot;How do we show we take abortion seriously?”

Today, NARAL Pro-Choice America is talking about a &uot;culture of responsibility and freedom” as a counterpoint to the &uot;culture of life.” It challenged pro-lifers to join in reducing abortions with birth control and sex education.

But what if Roe is overturned? Or is it time to say, when Roe is overturned?

In the early 1970s, this country was a crazy quilt of laws. Women traveled across state lines for their rights. If the issue goes back to the states where legislatures debate rights and

restrictions, pro-choice advocates have to find a better way to speak to the middle.

Abortion has been the greatest mobilizing force for the religious right. As the White House and the Congress were lost, abortion supporters depended too long and too hard on the court.

Now Mother O’Connor has pushed back from the table. The Justice of the Peace is retiring. The center doesn’t hold. We have to find our own way to avoid the collision course.

(Ellen Goodman’s e-mail address is ellengoodman@globe.com.)