Martin Peretz hugged Gary Hart. Then Martin Peretz hugged Henry Kissinger. And there you have it.

All this hugging took place at Peretz's celebration of the 70th anniversary of that bastion of liberalism, both classical and neo, The New Republic.

"It's a terrific magazine," said Hart of the publication that Peretz bought 10 years ago. "It is not a liberal magazine. This magazine understands something I've been saying for 10 years. The old labels don't work anymore."

So no one tried to label anyone. Liberal? Conservative? They were just people, more than 400 people like U.N. Ambassador Jeane Kirkpatrick, Sen. Daniel Patrick Moynihan, Commentary editor Irving Kristol, former presidential candidates Eugene McCarthy and Jerry Brown, and Rep. Barney Frank. "It certainly shows the ideological schizophrenia of the magazine," said editor Hendrik Hertzberg. "It's kind of a metaphor for the whole place, even down to the black-tie-optional."

We should all have such metaphors. And such Rolodexes.

One guest, crammed amidst several hundred tuxedos (most ignored the "optional"), said the scene at the National Portrait Gallery resembled a subway. All that was missing was the straps to hang from.

Which is just exactly what you want when you're celebrating yourself.

"Washingtown is a town," Peretz said in his toast, "where if other people don't arrange a testimonial for you or your institution, you can always arrange one for yourself."

As waiters balanced trays brimming with flowers and chicken and escargot hors d'oeuvres, newly born senators (Albert Gore Jr., John Kerry and Paul Simon) talked eagerly to reporters, and old friends from the academic world embraced. But it was basically a Washington political/media crowd, with the scale tipping toward the so-called "liberal": Sens. Bill Bradley, Max Baucus and Don Riegle; Reps. Henry Waxman and Tim Wirth; AFL-CIO chief Lane Kirkland; political consultants Patrick Caddell and Gerald Rafshoon; U.S. News & World Report publisher Mortimer Zuckerman; U.S. News editorial director Harold Evans (with wife Tina Brown, the Vanity Fair editor-in-chief); NBC correspondent Marvin Kalb; commentator Patrick Buchanan; New York Times bureau chief Bill Kovach; and Newsweek bureau chief Mel Elfin.

Actor Warren Beatty, whose name stood in splendid isolation on the invitation way above Kissinger's and McCarthy's, didn't show. "He got stuck in Paris for pressing personal reasons," said Peretz, stressing the word "pressing," and moving off to hug someone else.

Former Israeli ambassador Simcha Dinitz, novelist Renata Adler, filmmaker Fred Wiseman and the Rev. Robert Drinan, however, managed to make it, although the presence of Kissinger on the guest list surprised Drinan.

"I can't fathom that," he said. "I'm quite disappointed with The New Republic often. They're going too far to the right. They're kind of groping."

As further proof that even a nice little celebration of the magazine is a decidedly political event, former editor Michael Straight lambasted the planned party in a letter to The Washington Post earlier this month.

"Mr. Peretz's claim to represent the 60 years in which The New Republic was edited by Herbert Croly, Bruce Bliven, Gilbert Harrison and myself," Straight wrote, "is on a par with President Reagan's insistence that he is the inheritor of the tradition of Franklin Roosevelt."

Peretz chuckled earlier yesterday as he described his reply to Straight, who served as deputy chairman of the National Endowment for the Arts during the Nixon and Ford administrations and was recruited by Soviet spy Anthony Blunt into the communist underground in the '30s.

"I said that if I had been a volunteer in Stalin's espionage network, and ended up as a big enthusiast of Richard Nixon's," Peretz said, "I would not begin to challenge other peoples' liberal credentials.

"I must say I think it's a rather entertaining retort."

The evening's entertainment consisted of either giving a toast or talking while someone else did. As Frank, Bradley, McCarthy, Kristol, Betty Friedan and others rose to extol the virtues of Peretz and his magazine, the dining crowd moved through salmon stuffed with trout mousse, veal and the kind of chocolate dessert you rarely see in your own refrigerator.

The toasts, which went on and on and on, began with the reading of a letter, in the pleasantly laudatory tone familiar to all frequenters of Washington testimonials. By the time the reader reached, "Nancy and I join in sending . . ." the audience had caught on to the identity of the author and was laughing or, in the case of a few, offering faint hisses.

Then it was time for serious praise, and a little qualifying. "Seventy years is a long time for a magazine to survive," said Kirkland, "and the survival of The New Republic for that long is a sign that clean living, intellectual consistency and uniform good judgment are not essential keys to a long life."

The qualifications of the other side of the spectrum consisted of things like Kristol's comment that "I myself have been a reader of The New Republic for half of its lifetime, and I often learn a great deal from it, even if it is not exactly what the auditors and authors intend to teach me."

Writer Fran Lebowitz offered the iconoclastic message that "The only magazine I ever subscribe to is the National Inquirer, which in my experience is as accurate as any other magazine and somewhat more colorful."

Several guests praised the magazine for its support for Israel, support that can only be described as very stalwart. "Marty," Dinitz said, "if Golda was here with us tonight, she would have been mighty proud of you."

By the end of the evening, at least one hora had been danced on the marble floors of the Gallery, and Time magazine writer and former New Republic columnist Roger Rosenblatt had recalled that he and The New Republic's Michael Kinsley once decided to publish a "No Story About Israel Edition."

All the while, the distant tables that Frank referred to as floating somewhere in "the northeast section of the city" continued to vibrate with talk. It was only when a certain former secretary of state went to the microphone that the buzz died down, proving once again that if you speak slowly enough and deeply enough, and if your name is Kissinger, people listen.

"Let's face it," he said, "this is not my normal constituency. This evening has been traumatic for me. I have been photographed with so many liberals, my semiannual visits to the White House will now be even less frequent."