Just when I was sure she was out, I heard Ginsburg’s voice. “What would be the components of the injunctive relief that you would seek, assuming you have a Lanham Act claim?” she asked the lawyer who had been addressing the court.

Ginsburg sat up slightly, eyeing him through the top of her glasses. She interrupted his response with a follow-up.

She had been fully engaged the entire time.

As long as she can do that, Ginsburg is right to ignore the chorus of liberals asking that she retire and allow President Obama to replace her, in case Democrats lose the presidency in 2016. On Sunday, liberal former Justice John Paul Stevens told ABC’s “This Week” that although he’s not advising Ginsburg, he thinks it’s appropriate to consider politics in a retirement decision.

Nobody ages more publicly than Supreme Court justices. Chief Justice William Rehnquist endured a ghoulish deathwatch. It’s natural now that attention should fall on Ginsburg, at 81 the oldest on the court and a two-time cancer survivor. She has broken her ribs in falls, and has more than once drifted off on live television during a State of the Union address.

But Ginsburg has taken politics into account when contemplating retirement — and she told The Post’s Robert Barnes that “I think it’s going to be another Democratic president” elected in 2016. Regardless of 2016, is it a good idea to hound justices into retirement based on actuarial considerations? Liberals may need to push out Stephen Breyer (he has had a series of bicycling accidents) and Sonia Sotomayor, who is a diabetic. Conservatives may need to replace Anthony Kennedy (heart problems) and Chief Justice John Roberts (seizures) at the first opportunity.

The only consideration should be whether Ginsburg is still up for the job — and there could be little question about that Monday, as the court heard a pair of minor cases, about a “vulture” hedge fund trying to get money it’s owed by Argentina, and about whether Coca-Cola is misleading consumers with a picture of a pomegranate on bottles that contain 0.3 percent pomegranate juice.

Ginsburg, a wisp of a woman, entered the room slowly, trailed by Justice Samuel Alito, who towered over his stooped colleague by a good 15 inches. She wore her customary owlish glasses and leaned forward in her seat, her mouth slightly agape. While other justices rocked in their chairs, Ginsburg sat still, a pencil in her right hand, slumped low over thick stacks of papers. After the arguments concluded, Ginsburg rose with some difficulty and was the last justice to disappear behind the red curtain.

She spoke quietly, with frequent pauses and poor enunciation. “Pardon me, your honor?” Ted Olson, one of the lawyers arguing Monday, responded when Ginsburg asked him a question about Argentina’s banks. “I’m sorry?” Olson replied when she asked another question, about bondholders.

But throughout the morning, Ginsburg was prominent, persistent and persuasive. In the first case, she was the second questioner, after the always-talking Sotomayor. (Justice Elena Kagan, more deferential to her senior colleague, twice began to speak but backed off after hearing Ginsburg’s voice.) When Justice Antonin Scalia seized the floor from Ginsburg, she quickly took it back. After a second interruption by Scalia, she scowled and looked over at the offender.

Ginsburg made the case for Argentina better than the lawyer representing the country. The lawyer responded to her questions with, “That’s exactly correct, Justice Ginsburg,” and, “Absolutely, Justice Ginsburg,” then reminded other justices about what “Justice Ginsburg said” and the “examples that I and Justice Ginsburg were referring to.”

Her sharp questions had a way of turning the argument in her direction. After she told the lawyer for Coca-Cola that “it’s really very hard to conceive” that Congress intended the law to be interpreted the way the company had done, Kennedy, typically the swing justice, kept the focus on “Justice Ginsburg’s question.”

“I had the same concern,” he said. “And this is relevant because we want to see what the likely intention of Congress was.”

The oldest justice still has the juice.

Twitter: @Milbank

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