The defense establishment of both sides -- but mainly the Republican side -- turned out last night to honor someone who really has worked for both sides: arms negotiator Paul Nitze.

And while the likes of Defense Secretary Caspar Weinberger, former defense secretary Harold Brown, retired admiral Elmo Zumwalt, former ambassador Clare Boothe Luce, retiring Sen. John Tower (R-Tex.), and the video image of President Reagan eagerly rendered praise for Nitze, few wanted to answer the really provocative questions that many guests might have been mulling over. Like:

Will Weinberger remain secretary of defense?

If not, will Tower get the job?

The occasion was the Ethics and Public Policy Center's black-tie dinner -- attended by about 600 -- to honor Nitze with its Shelby Cullom Davis Award. The host was the center's president, Ernest W. Lefever, whose nomination by Reagan several years ago as assistant secretary of state for human rights provoked fierce opposition from human rights organizations and liberal Democrats in Congress and was rejected by the Senate Foreign Relations Committee before Lefever withdrew his name. Last night, that seemed to be far behind him as he eagerly greeted his guests and straightened his bow tie expectantly upon seeing Weinberger arriving.

The place was the Washington Hilton. And if these questions were floating around, this must be post-presidential-election mid-November Washington.

Asked if any more Soviet ships were steaming into Nicaraguan harbors, Weinberger said, "They come in and go out every day." He added later, "Well, sure it's something to worry about. But they come in and go out every day."

About the Defense post: "You'll have to ask the president," chuckled Weinberger. "There're just too many rumors floating around. Rumors, rumors, rumors . . ."

And Tower (thought to be keen on the Defense job himself) had a similar reaction when asked if he might get the job: "I've not the foggiest notion," he replied, adding diplomatically, "There's no vacancy in that position. We have a fine secretary of defense."

But does he want it?

He paused. "I'm not looking for a job."

His wife, Lilla, the former head of the Institute for Museum Services, said she was just looking forward to having time with her husband: "I'm threatening to buy him a bicycle," she said. "I want to take walks in the woods, see movies . . ."

And how does Sen. Tower feel about walks in the woods and seeing movies? He brooded for a moment.

"How about flying kites?" his wife added.

"I don't know about flying kites," he answered.

"He's so cute," she said.

Nitze, himself, the man who "turned a walk in the woods into a diplomatic event," in the words of last night's master of ceremonies, NBC News chief diplomatic correspondent Marvin Kalb, seemed to be the last person who wanted to talk about the progress of arms negotiations. Both the Intermediate-Range Nuclear Forces Negotiations, headed by Nitze, and the START talks headed by Edward Rowny -- both Geneva-based -- have been stalled since last December.

Nitze's remarks last night, however, were filled with anecdotal remembrances of posts and administrations past. There was the time in 1961 when Nitze was working with W. Averell Harriman in Harriman's office, and then-secretary of state Dean Rusk called on the phone: "Averell being deaf, I could hear what Dean had to say better than Averell could," recalled Nitze. "Dean asked Averell whether he would accept the job of assistant secretary of state for Far Eastern affairs. Averell said he would. When he had hung up, he asked me what job it was Dean had asked him to take."

His audience roared.

"It seemed to me," Nitze said about his remarks, "that this was an occasion not to be serious."

What does a negotiator do when no negotiations are underway?

"The government is marvelous," Nitze replied. "It keeps one fully occupied. One is reviewing all the possible contingencies in case the talks start again."

And Rowny was willing to make some predictions: "The Soviets are coming back to the table. It's in their interest. It's in our interest." But, he added: "You can't seem too anxious, because then they want to extract a price. But we'll be back. They'll be back . . . It takes two to tango."