Much has been made, and quite rightly, of the Reagan administration's decision to shut down some 91 "storefront" counseling centers for Vietnam veterans across the country. But that is only the first wave of the assult on Vietnam War veterans by David Stockman's Office of Management and Budget.

As if by the most careful calculation, OMB has gone through the federal budget and neatly exercised programs of the Labor and Education departments, as well as the Veterans Administration, specifically designed to help those who served in the military in the Vietnam years. Marked for extinction are efforts to hire the disabled; to find jobs for the unemployed; to promote education and vocational training; to deal with psychological readjustment; to ease the anxiety and provide medical attention for those fearful of exposure to the toxic effects of the dreaded herbicide Agent Orange.

Says one Vietnam veteran advocate in the Labor Department: "It's a wipeout of the only benefits that we were able to get in all of the last 10 years." Total savings: $70 million -- less than one percent of total VA outlays.

Now where, you might ask, does this special pleading fit into a column regularly devoted to foreign policy and matters having to do with national security? I would turn to President Reagan's own spoken record to make the connection.

"Because our national security is so dependent upon the people in our armed forces, we must do all in our power to assure that they are of the highest caliber," Reagan told the American Legion last year, in mid-campaign. "The key to building and retaining effective military forces is to encourage people to pursue a career in the services of their choice."

One way to "attract and retain superior people," he went on, is "to restore the GI Bill, one of the most effective, equitable and socially important programs ever devised."

True to his word, the president is supporting a new peacetime GI Bill to provide education and other benefits for the military veterans of the future. But in the very same budget he would strip away a provision that would have extended for another two years the expiration date of GI Bill education benefits for those who served in the time of the Vietnam War.

That is precisely the part of the connection between national security and public policy on the treatment accorded Vietnam veterans that the president and his budget-cutters can't seem to make. In their efforts to make military service more attractive, respectable, honorable -- to lay to rest that part of the so-called Vietnam syndrome -- the government would dangle the carrot of aid to education and other compensation for time lost and service rendered. The hope would be to avoid having to use the stick of conscription.

But just how enticing is that carrot likely to look to potential volunteers when, at the same time, comparable benefits for the most recent generation of veterans are among the first items singled out for budget cuts in a government economy drive?

You think the present generation of potential veterans won't notice? Perhaps. But it won't be for lack of effort by the Vietnam veterans, already thoroughly aroused by Stockman's handiwork. Their numbers, you could say, are relatively small: Some 9 million men and women were in uniform in the Vietnam years, of which about 2.6 million actually served in the combat zone.And it is often said that the Vietnam experience for most veterans was, in fact, not all that much stressful than in other wars.

But more than enough respected psychologists and psychiatrists have come up with persuasive evidence that just as the war was distinctively destructive, so was its emotional impact on many of those who were caught up in it and its aftereffects.

Last year, in his famous defense of the Vietnam effort as a "noble cause," Reagan was at pains to note that "we have been shabby in our treatment of those who returned." Last month, hailing their valor, he talked of Vietnam veterans, not as having been "defeated but as having been "denied permission to win."

Does it not occur to him that this experience alone must have taken some considerable emotional and psychiatric toll?

Psychologist John Wilson, director of a definitive study, "The Forgotten Warrior," argues that "appallingly few psychiatric people know anything about Vietnam veterans -- they are misdiagnosed, mistreated." He estimates there are a half-million or so alienated Vietnam veterans beyond the reach of conventional VA medical help.

Hence the 91 VA "outreach centers" in modest, unforbidding storefronts, manned largely by fellow Vietnam veterans.Those are the community-based operations David Stockman would disband, on the ground that the established facilities of the federal government can do the job.

That is not only "shabby." It is also an invitations for a "single issue" political outcry that, however indirectly, cannot help having serious repercussions for the military services -- and, by extension, for national security.