Much has been written in recent weeks about who among America's youth will be fighting -- and who will not -- if the United States goes to war in the Persian Gulf.

Mark Shields laments that the children of Washington's elite will not do the dying {op-ed, Nov. 2}, Time magazine explains "Why No Blue Blood Will Flow" {Nov. 26}, and John Kenneth Galbraith takes as a given that "deployed on the sands of Saudi Arabi and facing possible extinction, are young men and women drawn, in the main, from the poorer families of our republic." {New York Times, Nov. 7}.

Comments such as these, fueled more by anecdotes and impressions than by facts, show that perceptions of the volunteer military have not yet caught up with reality.

Two recent studies conclude that today's enlisted recruits (and most likely the troops in the Middle East) are broadly similar to the general youth population in terms of socioeconomic characteristics. The first, a 1989 Congressional Budget Office study, "Social Representation in the U.S. Military," examined family incomes and other characteristics of the home neighborhoods of recruits. The second, a Defense Department survey detailed in the latest edition of the department's annual report to Congress, "Population Representation in the Military Services: Fiscal Year 1989," asked recruits about such issues as the education and occupation of their parents.

In 1987, the latest year available for the CBO study, about 45 percent of active-duty recruits came from areas with above-average incomes, and 55 percent from below-average areas. A young man from a community with family incomes 20 percent below the average was only slightly more likely to enlist than one from an area with incomes 20 percent above average.

Only at the very upper end of the income scale was a substantial difference apparent: the 10 percent of American youth living in the country's richest communities were about half as likely to enlist in the military as those from the poorest communities. Statistics for the Army, the service likely to sustain the greatest casualties in any Persian Gulf conflict, closely matched those for all services combined.

The Defense Department study finds similar patterns in the characteristics it surveyed. For example, the parents of recruits in 1989 had virtually the same college-attendance rates (although somewhat lower graduation rates) as the parents of all enlistment-age youth.

The critics' claims of a sharply unequal burden of military service are roughly 10 years out of date. In 1980, more than 15 percent of Army recruits were drawn from the poorest tenth of American communities, and more than six out of ten from areas with below-average family incomes. Since that time, however, the Army has dramatically improved its ability to recruit high school graduates who score well on the military aptitude test, and as a result draws more heavily from higher-income areas. The proportion of Army recruits from the poorest tenth has fallen by more than one-quarter and the proportion from the highest tenth has increased by one-half.

The one clear difference between the personnel of today's military and the general population is the frequently cited overrepresentation of minorities -- particularly blacks -- in the military. Blacks accounted for roughly 22 percent of active-duty recruits in 1989, compared with about 14 percent of enlistment-age youth. For the Army, blacks accounted for better than one recruit in four. Compared with their share of all active-duty personnel, however, blacks are reportedly somewhat underrepresented among U.S. troops in the Persian Gulf.

Calling up the reserves will have a mixed, and rather modest, effect on the composition of the enlisted forces. The Army National Guard, which includes almost all of the ground combat troops in the reserves, has a somewhat higher percentage of whites than the active Army, but it also draws much more heavily from poorer, rural areas of the country. The Army Reserve, comprising primarily support units, matches the active Army fairly closely on both measures. Enlisted forces in the other reserve components are too few in number for their mobilization to have any significant impact.

Nor would a peacetime draft affect the situation very much. Certainly a lottery draft like the one instituted toward the end of the Vietnam War would ensure that some of Washington's elite would have an immediate personal interest in any Persian Gulf conflict, but the numbers involved would be small. Even if drastic measures were introduced to discourage volunteering, such as slashing pay for new recruits, projected peacetime recruiting requirements could be met primarily with volunteers. Draftees would account for less than 25 percent of recruits. As a result, in a military made up of both draftees and volunteers, blacks would still be overrepresented and higher-income youth underrepresented.

Are the sons and daughters of America's elite missing from the military's enlisted ranks? Perhaps, although more members of Congress reportedly have sons serving in the Persian Gulf than would be expected for a body with 535 members.

Are the children of middle- and upper-middle-class America missing? Almost certainly not. If this country ever had a military of the poor, it no longer does. Even the characterization of the Army as a "cross section of lower-middle-class America'' -- by Charles Moskos, an oft-cited analyst of the volunteer military -- does not appear to be accurate today.

The writer, a principal analyst at the Congressional Budget Office, is the author of "Social Representation in the U.S. Military."