The scene was strikingly reminiscent of the Carter administration heyday: Jody Powell consorting with Lady Bird Johnson, Zbigniew Brzezinski calling across the table to Lloyd Cutler, Andy Young signing autographs, and the familiar Carter aides overprotecting everyone.

And then, The Arrival.

Jimmy and Rosalynn Carter reappeared on the Washington social whirl last night after nearly a year of self-imposed absence.

"This is where he belongs," said Brzezinski. And then, with typical droll humor: "After dinner tonight, everyone here is going to march down to the White House and seize the government."

The black-tie, heavily Democratic tribute dinner for Averell Harriman, benefitting the National Mental Health Association (NMHA), culminated a two-day visit here by the former president and first lady. Everyone last night acted as if he were still the president.

"I haven't missed it at all," said Carter, flashing The Grin. The "it" was Washington. "Rosalynn and I have found life in Plains very pleasant, and we've had no yearning to be back. Some weeks of the year I do have a yearning to be back at Camp David."

Everyone hugged and kissed the See HARRIMAN, B10, Col. 3 HARRIMAN, From B1 Carters and each other and tried to pretend that it was a bipartisan event -- which was sort of hard to do, given the statistics. There was at least one token Republican in attendance.

"As I look over the head table here," surveyed Sen. Charles Percy (R-Ill.), "it becomes obvious that we could hold our next convention in a phone booth."

Carter appeared very relaxed and in good spirits as he caromed around the Sheraton Washington ballroom glad-handing with all the faces from yesteryear. He seemed slightly out of sorts only once, when a reporter abruptly questioned his feelings about Ronald Reagan.

"We get along just fine," he said, turning his back.

In his remarks about Harriman, Carter commented that he first became intrigued with Harriman through political history and was amused when a congressional hearing text described him as "an ambitious 70-year-old man."

"In 1976 I thought that was funny," smiled Carter. "In 1980, I was no longer laughing at 70-year-old ambitious men." The crowd cackled for two minutes.

But political banter didn't dominate the night. It was Averell Harriman's evening and he was having a ball. In addition to Carter, Percy, pianist Peter Duchin and Harriman's stepson Winston Churchill II all paid tribute to the 89-year-old statesman. Churchill, Pamela Harriman's son through her marriage to Randolph Churchill, flew to town from London just for the evening.

The Harrimans and the Carters have long been crusaders for mental health, Rosalynn Carter making the cause one of her pet projects as first lady. Last night's event raised over $120,000.

"Mrs. Carter was responsible for drawing so much attention to it," said NMHA president Archie Givens. But being a realist, Givens added, "With all the inflation and economic problems around, I think people are just more attuned to mental health. Everyone is getting depressed and now its okay to admit it."