WASHINGTON — At the recent annual spring dinner of the Gridiron Club, the U.S. Marine Band in all its John Philip Sousa magnificence launched into a medley of service anthems, from the Army's "Caissons Go Rolling Along" to the Corps' own "Marines Hymn."

In this room filled with the nation's leaders, including the president, vice president and members of Congress, as well as publishers, movie and television celebrities and others, the red-coated Marines always provide a stirring moment in a night filled with the journalism club's roasting of the political parties in song, dance and speech — a sometimes anachronistic, but hugely necessary, long-running display of irreverence.

There is always a shifting of bodies in the room as the band, after performing one of Sousa's stirring marches — on this night it was the "Gridiron March" — strikes the first chords of the service medley. Proudly, veterans of the Army, Navy, Air Force, Marine Corps and Coast Guard prepare to rise to attention as the trumpets blare and the notes fill the hotel room. Forty years ago, large numbers of the audience stood fiercely proud, perhaps remembering the roll of a ship or the roar of an airplane engine or a landing craft's pitch as it headed for a beach.

As the years have passed, however, the number of those who rise has dwindled steadily, the ranks thinned by natural forces and not refilled, until by this night there were only a handful of gray, balding and often-stooped men throwing back their shoulders to stand tall against the ravages of time in honor of their heritage and their fallen comrades.

This, of course, should surprise no one in this age of a volunteer military. This should not be construed as any criticism of the young men and women who have committed themselves willingly to stand guard over the rest of us. Nor is it an appeal for the return of the draft. It is merely an acknowledgment of the passing of a tradition of shared experience that has linked men and women since the beginning of the Republic, a nod to the citizen warrior whose dedication, whether in peace or combat, through willing enlistment or conscription, has never been found wanting.

As the last drum roll reverberated and the band departed to a thunderous ovation, more than one in the audience expressed a sadness at the waning of a tradition and wondered if it is a loss the nation can truly afford. The answer, of course, is that there still are young men and women who understand the important role of part-time service, those who meld a civilian career while giving up weekends and other time to fill important jobs in the reserves or National Guard.