If you want proof that we’re living out Disney’s post-princess era, take a look at what’s not happening in our race for the U.S. Senate.

Sam Nunn, the venerable former U.S. senator, on Thursday said you won’t find him polishing up his rusted armor and mounting his aged steed to rescue his daughter from GOP charges that she served as a banker for terrorists.

Michelle Nunn, the Democratic candidate for his old seat, has it covered, her father said. He pointed to a 30-second TV spot in which his daughter looks dead-on into the camera and labels the accusation from Republican rival David Perdue “a terrible lie.”

In that sense, you could consider the ad a political version of “Let It Go.” (If you have daughters or granddaughters, you understand the cultural reference. If not, you’ve got some research to do.)

“I think her firmness and her response — labeling it a complete fabrication, a lie — and her delivering that message directly herself is the way to go. I think she’s done it very well,” Sam Nunn said.

But in truth, the Nunn response to the sharpest attack in the race for the U.S. Senate has less to do with Disney’s “Frozen” and more to do with the 2002 contest between U.S. Sen. Max Cleland, the Democratic incumbent, and Republican challenger Saxby Chambliss — who is now headed for retirement.

That October, little more than a year after the 9/11 disasters, the Chambliss campaign launched a 30-second television attack on Cleland that was introduced with images of Osama bin Laden and Saddam Hussein.

The ad challenged the courage of Cleland, who lost three limbs in Vietnam, and criticized him for blocking legislation to give President George W. Bush unlimited hiring and firing power over the new Department of Homeland Security.

The outrage was palpable. Then-U.S. Sen. John Kerry, D-Mass., called the ad “garbage.” Cleland declared it an attack not just on his honor, but “the very fiber of my being.”

Yet the reaction was neither sustained nor organized. And in the end, the now-famous attack ad sullied Cleland’s aura of self-sacrifice. He lost his re-election bid.

By contrast, a dozen years later, the Nunn reaction to a similarly volatile charge has been patient, cold-blooded and relentless.

Michelle Nunn and her Points of Light Foundation, founded by President George H.W. Bush, stand accused of “giving money to terrorist-linked” Islamic organizations by the Perdue campaign.

Never mind the obvious Bush connection. Michelle Nunn is the daughter of one of the nation’s foremost national security experts. The charge cuts to the heart of her family identity. Hence the care her campaign has taken to debunk it.

The job has been made harder by the fact that the wound was, in part, self-inflicted. A Nunn campaign memo, which noted potential Points of Light activity that might be contorted into a line of GOP attack, was accidentally posted online. Republicans obtained a copy — and have used it ever since as a license to fulfill Democratic fears.

The first TV attack ad, paid for by a Super PAC, came in August. The Nunn campaign then had to wait for various news organizations, including The Atlanta Journal-Constitution’s PolitiFact, to do their fact-checking. (PolitiFact has given the charge a “Pants On Fire.” The Washington Post has awarded it a maximum four Pinnochios.)

Then came the condemnation from Neil Bush, a son and brother of former presidents and the chairman of the Points of Light Foundation. That was trickier. The younger Bush apparently had to wait for George H.W.’s coming endorsement of Perdue — so that he would not appear to contradict the ex-president.

“To attack an organization founded by my father, whose integrity is unimpeachable, to smear our organization for political gain, is in my opinion shameful,” Neil Bush said in September.

By this time, Perdue had incorporated the “terrorist” accusation into his own TV attacks on Nunn.

Which led to the aforementioned Nunn ad, released last week and still airing. It includes no mention of family honor. “It’s a terrible lie and an insult to the millions of volunteers I worked with to make a difference,” Nunn says.

Then, and only then, did Sam Nunn make himself available to a reporter and address the topic — using the same, specific language as Neil Bush, a Republican. “I don’t think there’s anything I can add to that,” the elder Nunn said.

If a TV camera is pointed at the dad, he might say something more. But you won’t see him in a 30-second spot. His daughter must be seen defending herself.

Sam Nunn has taken on the role of supplementary debunker. “It’s shameful. Particularly when you know that everybody in the opposition campaign knows that that’s not true,” he said Thursday. “It’s not like they believe it.”

The former senator says he has a friend in Houston County — the Nunns and Perdues both hail from there. “He says his friends supporting (Perdue) are just laughing about it — and that’s been for the last two or three weeks. They think it’s basically preposterous. But there are some people who will believe it. And that’s the reason they’re running it.”

I published Nunn’s remarks on the Internet on Thursday evening. On Friday morning, Tim Bryant, the radio talk show host for WGAU (1340AM) in Athens, had David Perdue on the line.

“Do you believe that Michelle Nunn is in anyway associated with terrorist organizations?” Bryant asked Perdue.

“Well, that’s what it says in their plan, Tim,” the Republican responded.

On Tuesday, Perdue and Nunn will meet at the Georgia National Fairgrounds and Agricenter in Perry for a first, full-fledged debate. Libertarian Amanda Swafford will be there as well.

The event sponsored by WMAZ-TV is always a raucous one. It will be a prime opportunity to see whether the home folks believe that the daughter of a favorite son has been rubbing shoulders, as Republicans say, with elements of terrorism.