They have lived so long they are watching the world forget.

These Holocaust survivors — who range in age from 79 to 101 — gathered for an annual brunch Sunday in suburban Washington, where they were honored in the twilight of their extraordinary lives for what they had endured and how they had rebuilt in America. There were white rose corsages and boutonnieres, bagels and lox, a nice fruit salad.

But the past was not in the past. Hours before the gathering, a neo-Nazi rally was held in Georgia that ended with the burning of a giant swastika. In August, the Holocaust survivors watched white supremacists and neo-Nazis march in Charlottesville, chanting chilling anti-Semitic messages right out of the Hitler playbook: “Jews will not replace us” and “Blood and soil.”

Edith Mayer Cord, 90, who was born in Vienna and spent her youth hiding and then escaping while family members were taken to Auschwitz, said she never imagined Nazi flags would fly in America in her lifetime. Or that rising anti-Semitism would be part of the national conversation.

“No. I never,” Cord said. “Not in this country.”

“I thought it was finished,” she said.

Yet over the weekend, President Trump tweeted about “Sleepy eyes Chuck Todd,” the NBC “Meet the Press” host who is Jewish. That is one of Trump’s favorite insults for Todd and one of the descriptions that has been hurled at Jews in the past. It has been on horrifying “How to Spot a Jew” lists since World War II and all over racist, white nationalist websites.

Trump has been accused of anti-Semitism before, especially in the wake of Charlottesville. Though the president has Jewish grandchildren, he seems to have lots of sympathy for virulent anti-Semites.

Then there is D.C. Council member Trayon White Sr. (D-Ward 8), an elected official right here in the nation’s capital, who wondered aloud last month whether the Rothschilds — a wealthy Jewish banking family often accused of controlling governments — are somehow controlling the weather, too.

After White was accused of rank anti-Semitism, he launched an apology tour and agreed to a guided visit to the U.S. Holocaust Memorial Museum for some much-needed education.

During the tour last week, Washington Post reporter Peter Jamison saw White insist that a woman in a 1935 photo being publicly humiliated and marched through her German town by Nazi stormtroopers was being protected.

One of White’s aides, in front of a photo of the Warsaw Ghetto, likened it to “a gated community.” The patient tour guide told them it was “more like a prison.”

By then, White had ditched his tour and his guides and left the museum without explanation, halfway through the visit.

Then, The Post’s Fenit Nirappil learned that White had given a $500 donation in January at a Nation of Islam event where Louis Farrakhan said, “Powerful Jews are my enemy.”

When Joel Appelbaum began the survivors’ brunch at the Charles E. Smith Life Communities in Rockville eight years ago, it was in the spirit of honoring the people and their remarkable lives.

There were 50 of them, and very few wanted to talk publicly about their experiences, but they gathered and told small snippets of their stories to tablemates.

That is part of the survival, packing it away. Because how can you live a life of paying bills, doing dishes, raising the kids and sitting at a desk if you keep remembering the Nazi stormtroopers who machine-gunned everyone in the house while you — tiny, terrified you — hid in the closet during the bloodbath? If you keep lingering on the moment when half the people you were with were marched out to the freezing river, shot and thrown into the current when you were just 5 years old? If you remember the packed, hellish train to Auschwitz, during which 70 people in the train car died and you were one of 40 who survived — only to face the horrors of a death camp?

There is a new urgency in remembering those stories.

Two-thirds of American millennials polled did not know what Auschwitz is, and 22 percent had not heard of the Holocaust or were not sure if they had, according to a new survey conducted by the Conference on Jewish Material Claims Against Germany.

In their sunset years, the incredible Maryland survivors are opening up.

A handful of them went to the microphone at the Progress Club in Rockville on Sunday and told small stories they had not told before. Because something has changed in this country.

Not that it is easier.

Josiane Traum, 79, still choked up as she talked about the incredible act of bravery by her mother, Fanny Aizenberg, who lived through all the signature horrors of the Holocaust — from beatings by the Gestapo, to time in Auschwitz as a laborer and medical experiment subject — after giving her little daughter up to people who said they would hide her.

“My mother was so brave,” Traum said. “My mother gave me up and didn’t know if she’d ever see me again. . . . I am really, really lucky.”

They did see each other again. They sat next to each other at the brunch, representing the alpha and omega of the survivors’ age range, 79 and 101.

Aizenberg, the grande dame of the survivor’s group who still volunteers at the U.S. Holocaust Memorial Museum once a week, refuses to be called a hero.

“People tell you how they survived? They always ask me, ‘How did you survive?’ ” she said, in between brunch bites. “No one can tell you how they survived.”

“I don’t know how I survived,” she said.

The horrors are so profound. The stories grotesque and cruel, especially when told in a setting of china and stemmed water glasses.

The horrors are not gone. Never has that been clearer with this group than now.

“Nazism isn’t something that just happened one day because of one bad guy,” Cord said. “All of these ideas were there — all he had to do was pick them up.”

All of those ideas are still here. But we must never, ever let anyone pick them all up.

Never again.

Twitter: @petulad

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