"The thing that is amazing is that it did happen -- and it does happen."

Oleg Sokolov, minister counselor at the Soviet Embassy, was talking about the Chautauqua meeting last summer between Russian and American officials. But he could just as well have been talking about their Potomac "meeting" yesterday.

It was a typical Sunday afternoon mix-and-mingle brunch. You know the rules: Everybody crowds into the smallest room in the mansion, then proceeds to shout at each other. Providing background noise was a continuous showing of a videotape on the Chautauqua meeting. Nobody was watching.

What was amazing at the brunch was that it was hard to single out the Russians, either by accents or tweed jackets.

"I think it's a very good party," said Sokolov, casting a practiced eye over a crowd that included two senators, an assistant secretary of state, a television correspondent and a Broadway actress.

Sokolov paused long enough to watch a segment of the hour-long film, which 212 PBS stations around the country will show tonight but which audiences in Washington and New York will not see until March 18. The scene was from the debate at the Chautauqua meeting between Sokolov and Assistant Secretary of State R. Mark Palmer, moderated by John Wallach, foreign affairs editor for Hearst Newspapers.

"We didn't really want to score any points, just give our positions," Sokolov said.

Wallach organized the Chautauqua Conference on United States-Soviet Relations. He said it was the first time since Mikhail Gorbachev became general secretary that Soviet officials and Reagan administration policymakers agreed to debate before an audience that turned out to be several thousand Americans.

"They asked tough questions. It was an experience in democracy and the Russians got a bath," Wallach said.

Sokolov said the questions "were tough," but it was a "useful exercise."

So useful, apparently, that the Soviets announced at the party -- given by Esther and Jack Coopersmith -- that there will be a reciprocal engagement next summer in the Soviet Union.

Wallach has been asked to organize a delegation of American policymakers, academics and artists to meet with their Russian counterparts in September. Singer-actress Karen Akers has agreed to go and yesterday she said she was told she's not only supposed to sing, but also read poetry. Last fall at Ford's Theatre, Akers read the English translation of poems by Soviet poet Andrei Voznesensky.

"We became fast friends," Akers said of Voznesensky, whose poem about Chautauqua was printed on the front page of Pravda this winter.

Sen. Edward Zorinsky (D-Neb.) said Wallach had asked him to be one of the Americans on the delegation this fall. He said he liked the idea that there is no official stamp on the get-togethers. "It takes the propagandizing syndrome out of it," he said.

Valeriy Chibisenkov, whose delegation was invited to the United States by the Citizen Exchange Council of New York, said he was enthusiastic about the prospect of a recriprocal meeting. But he was less enthusiastic about "our children coming to your country, where you have crime, drugs and AIDS."

"You don't have those problems, any of that in your country?" a reporter asked.

"Not yet," he said, without explaining whether he meant just AIDS -- the Soviet Union has not admitted to any AIDS cases -- or whether he meant Russians are immune from crime or drug problems as well.

Valery V. Lekarev, third secretary of the Soviet Embassy in Washington, called the PBS special "a great beginning."

Would there be any interest in showing it in the Soviet Union? "It depends on whether you let it go or not," he answered. Wallach said the TV program has been offered to the Soviets.

Soviet guests at the brunch, who proved they could mix and mingle with the best of them, should have felt right at home. Next to the prebrunch cheese board were shot glasses and bottles of Stolichnaya vodka (for Democrats there was a Napa Valley cabernet sauvignon labeled "National Democratic Convention, San Francisco").

Esther Coopersmith didn't stop at being just a hostess. She also cooked blini, stuffed cabbage and typical Russian fare that surprised and pleased the Russians, apparently not quite sure what they would face at a Sunday Potomac brunch.

She also sent them back to Moscow with some heavy wool socks for her son Jonathan, a student at Moscow University, and gave each of them sample packages of freeze-dried "astronaut" ice cream.