The recent identification of the "unknown soldier" of the Vietnam War has focused attention on the significance of one of America's most hallowed shrines. The remains heretofore considered "unknown" have turned out to be those of Michael J. Blassie, an Air Force officer.

That revelation has created a serious problem. So serious, in fact, that Defense Secretary William Cohen is finding it advisable to consult with both Congress and veterans' groups as to what to do next, since the chamber dedicated by President Ronald Reagan on Memorial Day 1984 may soon be empty.Few people take issue with Secretary Cohen's decision to order a DNA analysis of the remains in response to demands of Blassie's relatives, who were unconvinced that the remains were indeed unidentifiable. The emergence of new genetic tests made a positive identification possible. In light of that development, the rights of the family have taken precedence.

The problem is what to do next. Should the tomb remain empty, as some have advocated, or should another set of remains, anonymous even with the help of modern science, be found to replace those removed? Much can be said on either side of that question.

The Tomb of the Unknowns is the shrine that carries more significance for me than any other - it is more important than those monuments erected to individuals, to military organizations or to veterans in general. I have a sentimental attachment to it, for when I was a youngster growing up in Washington, only a decade after the end of World War I, the Tomb of the Unknown Soldier represented to my family a spot of sacred ground. To me it remains the most revered of shrines.

Its significance is staggering, going to the very core of how a democracy defends itself in a perilous world. The tomb is not a memorial to generals and admirals - they have been celebrated enough - but to the soldier, in the broadest sense, who lays his or her life on the line with every ground attack, every air mission and every sea voyage in hostile waters. Those countless men and women, the vast majority of them unsung, are the ones who make the greatest sacrifice.

Our country has been created by numerous wars, but we are not a warlike people. Our citizens would like nothing better than to stay home with their families. If required to go to war, they long for the day when they are reunited with their spouses, sons and daughters. But even in the Persian Gulf War, our active troops, powerful though they were, still required the assistance of numerous civilian soldiers, reservists taken from their homes, families and jobs.

Monuments to fallen soldiers drive home to us what democracy means. We can visit shrines to great leaders and be filled with respect for what those individuals stood for, but it is in places like the cemetery at Omaha Beach in Normandy that mature men, tough men, break down and cry unabashedly. They are weeping for those who have all become, in a way, unknowns.

It has been pointed out that science will soon make true unknown soldiers a thing of the past; all remains will be identifiable. That may be so. But to me it is unimportant. I, for one, would have been quite content to let the Unknown Soldier of World War I represent all our hallowed dead.

Let us hope that the occasion for a new space at the tomb will never arise again. But in the meantime, the problem being faced by the authorities is a real one, close to the hearts of the American people because it involves feelings still alive. It deserves all the intense attention it is receiving.