Vice President Quayle, whose stateside service in the National Guard during the Vietnam War sparked a campaign firestorm two years ago, said yesterday that those who fought in Vietnam "made a sacrifice for their country that was far, far greater than mine."

In a speech to families of servicemen still missing in Southeast Asia, Quayle made rare, if brief, reference to the subject that badly damaged his candidacy in 1988. And for the first time Quayle explicitly acknowledged a personal gratitude to those who experienced combat while he did not.

Quayle called Vietnam veterans "heroes" and said that "for the rest of my life I will live in admiration of their courage." He described the war as "a noble effort and a just cause."

But he remained resolutely unapologetic about his tenure in an Indiana National Guard unit that did not go to Vietnam. Quayle joined the National Guard in 1969, served six months' active duty and 5 1/2 years in the reserves. Shortly after then-Vice President Bush chose Quayle as his running mate in 1988, allegations arose that Quayle had used family influence to enlist in the Guard and avoid the draft. The charges were never proven and the Bush-Quayle ticket was elected easily.

The resulting furor and intense scrutiny of Quayle, however, prompted most political analysts to characterize him as a severe liability to Bush during the campaign, and created political vulnerabilities that most analysts believe Quayle has yet to overcome.

"As you know," Quayle told a meeting the National League of Families of American Prisoners and Missing in Southeast Asia, "during the Vietnam era I served in the Indiana National Guard. . . . I did not serve in Vietnam.

"And while I have not apologized, and never will, for my National Guard service, I recognize that the members of my generation who served in Vietnam made a sacrifice for their country that was far, far greater than mine. The men and women who served in Vietnam were heroes. Not just because of their deeds of valor, but because they served at a time when words like 'duty,' 'honor' and 'country' lost their meaning for many."

Most of Quayle's speech concerned the Bush administration's efforts to account for the 2,302 military personnel still missing in Southeast Asia, with Quayle promising that "we will never forget" those unaccounted for. He was interrupted several times with polite applause, but did not take questions from the 250 people in the Washington hotel audience after his speech.

Quayle reiterated his belief that, even though he did not fight in Vietnam, he believed then and still believes the war was right.

"With the passage of time and the wisdom that time bequeaths," he said, "all Americans will recognize that {the war} was a noble effort and a just cause."