The secretaries of state and defense, who said they aren't feuding, went to a ball last night for the American History Museum's George Washington exhibit. Secretary of State Alexander Haig had dinner there, announced that he and Secretary of State Caspar Weinberger "always kiss and make up," then left. Shortly thereafter Weinberger arrived, said he and Haig had a "fine breakfast" yesterday that continued their "fine relationship," then set off for a tour of the exhibit which includes such things as George Washington's trousers.

Roger Kennedy, director of the museum, was his guide. Along the way, Kennedy pointed to modern-day ads and posters that pictured Washington--or "G.W.," as they've been calling him at the museum.

"He should have sued for an invasion of privacy," said Weinberger, who recently complained that the press quoted him inaccurately about a possible sale of U.S. weapons to Jordan.

"We use him to sell teeth, we use him to sell underwear," said Kennedy, pointing to more posters.

"Absolutely incredible," said Weinberger.

The ball for "George Washington--A Figure Upon the Stage" was enormous; 1,300 people celebrated the 250th anniversary of Washington's birth on two floors of the museum. It was paid for by United Technologies, Haig's former civilian employer. Guests ate ham rolls, cheeses and water crackers from tables set up in front of the Atom Smasher exhibit or The Art of the Instrument Maker, 1150-1850. Most were United Technologies people, exhibit donors, Smithsonian Associates and the like.

Haig didn't hobnob, but did pop off a line before leaving. He said he'd called Massachusetts General Hospital to check on former secretary of state Henry Kissinger after his recent heart bypass operation. Haig has had one, too.

"I talked to the doctor," said Haig. "He said he Kissinger was fine, except that he had had a personality change. He had come out arrogant, self-centered, egotistical and turf-conscious."

Dress for the ball was black-tie, interpreted loosely in some cases. "I'm Lady Fairfax," said Gail Schlaifer, 30, who was dressed in a large wig and ruffled dress and described herself as an artist and actress, although she said word processing pays the bills. "Lady Fairfax was supposedly George Washington's mistress, but she was married to Lord Fairfax, so there were a few problems. He met her before he met Martha, but I think they kept in touch."

By 10:30 p.m., the Virginia Reel started. The modern Americans watched as the performers made their way across the floor. Roger Kennedy watched, too. It would be safe to say he was in his element.

"This nation is a miracle," he said. "Look where we are--standing under the Star-Spangled Banner, with people of all ages and all colors. It's marvelous. That's the Star-Spangled Banner." It was. The museum displays the original.

"George Washington was not Napoleon," said Kennedy. "That was all about achieving power through mass murder. This guy held a nation together, managed a limited war and a limited presidency. And helped his nation survive it."

At midnight there was a fireworks display.