The U.S. Army today may be the world's largest and most successful equal opportunity employer.

The reason is not presidential proclamations or racial recruiting, but the national decision after Vietnam to switch from the draft to an all-volunteer military force.

Blacks, out of frustation and pride, joined this all-volunteer peacetime Army in unprecedented numbers, comprising 33 percent of those who signed up in May and 27.7 percent of the total enlisted force.

Less well-known but perhaps more important is that the blacks joining the Army now have more education than those whites who are joining. Also, the blacks now rising within the noncommissioned-officer corps are making the Army a career more often than white top sergeants, meaning black NCOs will be at the heart of such Army leadership in the future.

Disproportionately high unemployment among young blacks - 37.1 percent in June for blacks aged 18 through 19 compared to 11.9 for whites of that age - and limited opportunities have made the authoritarian Army look to many blacks as the best employer in sight.

"Wasn't nothing else to do out there," said Spec. 4 Alvin Smith, 23, of Jacksonville, Fla., during a recent interview at Fort Meade, Md. "I had jobs, but the only ones advancing in them was the white guys, especially where I'm from. Being in Florida you had a lot of prejudice going on."

Or hear Sgt. Terry D. Gilchrist, 24, of Augusta, Ga. "I kept watching TV and I kept seeing this $288 a month," he said. "I was working at the time, and that was as much money as I was making. I figured I could go in the Army and learn a trade and save some money."

Or Spec. 5 Clarence A. Randal, 25, of Toano, Va.: "I reenlisted because another job fell through. So rather than gamble, I reenlisted because I had a sure thing here. I got a wife and family, and I got to provide for them, too."

Some Army officers, however, fear the post-Vietnam military has over-sold the job opportunities of the service, encouraging a 9-to-5 attitude among soldiers who may have to fight one day.

Army Secretary Clifford L. Alexander, the first black to hold the job, and Charles C. Moskos Jr., a Northwestern University sociologist who has made a specialty of studying soldiers, see both bad and good news in the Army's racial trend.

The positive implication of the large number of blacks joining and remaining in the Army, Alexander said, is that young blacks perceive the Army as a way out of the nation's economic cellar.

The bad news, he added, is that those soldiers who make it to the top of the Army apparently stay in because "either they know or perceive that they wouldn't get the kind of opportunity and challenge and upward mobility on the outside that they do in the Army."

Although it is "helpful" to the Army, Alexander continued, "it's a negative statement about the private sector, either its actual employment or its perceived employment. Nobody out there is talking about employment opportunities for minorities."

Moskos said in an interview that blacks regard the Army as a way up and will continue to as long as a disproportionate number of them remain trapped in the cities from which there has been a flight of maunfacturing jobs."

One irony Moskos sees in the all-volunteer Army, which started after the last draft call in December 1972, is that it is attracting blacks with more education than their white counterparts. "That really is a very significant finding," Moskos said.

"The Army is the only arena in American society where blacks greatly exceed the educational level of whites."

With their edge in education and their higher reenlistment rates, the leverage of blacks on the Army would seem destined to increase, Moskos said he has already detected a white backlash in the ranks.

The Northwestern sociologist, in a lecture in January, elaborated on the phenomenon of black gains in the nation's military:

"Whereas the black soldier is fairly representative of the black community in terms of education and social background, white entrants of recent years are coming from the least-educated sectors of the white community.

"My stays with Army units also leave the distinct impression that many of our young enlisted white soldiers are coming from nonmetropolitan areas. I am even more impressed by what I do not often find in line units: urban and suburban white soldiers of middle-class origins.

"In other words, the all-volunteer Army is attracting not only a disproportionate number of minorities, but also an unrepresentative segment of white youth . . ."

Moskos cited these Army figures to show the Army is signing up three black male high school graduates these days for every two white graduates:

Fiscal year High school graduates(TABLE) (COLUMN)Black(COLUMN)White 1974(COLUMN)47.6%(COLUMN)46.2% 1975(COLUMN)49.4(COLUMN)46.9 1976(COLUMN)63.6(COLUMN)47.1 1977(COLUMN)60.5(COLUMN)40.0(END TABLE)

The following Army figures show further that far more black soldiers have been reenlisting than whites since the draft ended.

FIRST REELISTMENT(TABLE) (COLUMN)Fiscal year(COLUMN)Blacks Whites 1972(COLUMN)17.3%(COLUMN)12.2% 1978(COLUMN)46.3(COLUMN)27.1(END TABLE)

TWO OR MORE REENLISTMENTS(TABLE) (COLUMN)Fiscal year(COLUMN)Blacks Whites 1972(COLUMN)61.3%(COLUMN)42.6% 1978(COLUMN)78.0(COLUMN)65.3(END TABLE)

While the gains blacks have made in the Army are the most impressive because they involve the most people, all the military services have registered increases, as these Pentagon figures for fiscal years 1968 through 1977 show:

Army - Percentage of black officers and enlisted people roughly doubled from 3.3 percent to 6.1 percent for officers and from 12.6 percent to 26.4 percent for enlisted.

Navy - This traditionally lily-white officer corps went from 0.4 percent black to 1.9 percent in the 10-year period while black representation among enlisted people rose from 5 percent to 8.7 percent.

Air Force - Black officers increased from 1.8 percent to 3.2 percent, while black enlisted rose from 10.2 percent to 14.7 percent.

Marines - Black Marine officer representation went up fourfold, from 0.9 percent to 3.6 percent in the 10 years, while black enlisted climbed from 11.5 percent to 17.6 percent.

Given the fact that the blacks joining the Army have more education proportionately than their white counterparts, Moskos raised the paradoxical concern about blacks getting a poor impression of whites.

"People are always talking about white stereotypes of blacks," said Moskos. "What about black stereotypes of whites?"

For a respected university sociologist to be worrying about the impression whites make on blacks in the Army cannot but taste bittersweet to a black sergeant major at Fort Meade who has lived through the indignities in the military world he longed to join ever since boyhood.

Standford Bryant, the sergeant major, recalled during an interview in the provost marshal's office he runs at Fort Meade that in 1960, a full 12 years after President Truman had ordered "equality of treatment" within the armed services, a white captain dressed him down for asking when he was going to get promoted.

President Truman on July 26, 1948, issued Executive Order 9981 stating "it is declared policy of the president that there shall be equality of treatment and opportunity for all persons in the armed services without regard to race, color, religion or national origin . . ."

When he joined the Army in 1953, Bryant said, "you'd never see a black first sergeant. You'd never see a black officer in command of anything. The ranking black officer you might see would be a colonel . . . but he would be a chaplain."

"In today's Army you simply cannot be accused - even if you're innocent" - of telling a soldier he will not get ahead because of his race.

"As a black sergeant major, if I have a white kid come in (and) say I discriminated against him, even if it is proved to be an unfounded accusation, it still would worry the hell out of you."

One reason for worrying, Bryant said, is that such a complaint would indicate that the troops perceive their sergeant is prejudiced. "If I think you're prejudiced, and I charge you with prejudice because you didn't give me a pass or you didn't put me in for promotion, you're going to be looked at."

The days of blunt, visible chargeable discrimination against blacks are over for the Army, in Bryant's view. But subtle discrimination persists and will continue to persist, in the sergeant major's opinion. Racism toward people of other cultures is a worldwide phenomenon and is not about to go away, he believes.

"The young black soldier today finds it extremely difficult to understand the subtle racism that he has to deal with," said Bryant, who has counseled hundreds of black soldiers in his job as "top" sergeant.

"He looks at the white sergeant and expects him to call him a nigger." If he doesn't, continued Bryant, some of the young black soldiers look for the expected prejudice elsewhere. If a white sergeant assigns a black to clean latrines, that young soldier, having failed called "nigger," or "boy," may conclude: "He told me to clean the latrine up because I'm black."

This suspicion - shared by whites toward black sergeants as well - puts a strain on both black and white non-commissioned officers.

"I'm prejudiced," said Bryant. "Everybody is prejudiced to a degree. But if a young soldier, black or white, does his job, meets his responsibility in the military, he can go just as far today as any other soldier. This was not the case before."

The world of Stanford Bryant - the black who beat the old system by rising from private to sergeant major and believes "the good old days" are really today - has been the world of the enlisted man.

Across the flat expanse of Fort Meade, in a tall brick building dominating the landscape, another black from the world of the officer corps runs the staff of the First U.S. Army. He is Brig. Gen. George B. Price.

Price, like Bryant, believes the military is ahead of other U.S. institutions in providing equal opportunities for blacks. But he is worried about the future on two counts: that military will consider the race problem solved and let the special programs to combat racism wither until there is another crisis; that the military will run sort of qualified black officers in the near future.

"The equal opportunity and the affirmative action programs have sort of taken a back seat in everybody's mind because the black soldier is not raising a hundred dollars' worth of hell. But he is capable of doing that.

"We have to recognize the calm before the storm," said Price. "Statistically, we're doing great. But statistically we won the war in Vietnam. The silent majority has never left us" and therefore racism could polarize blacks and whites again if the problems are not kept under attack, he said.

"I do believe we're just a little complacent. We're looking at statistics" at the very time "institutions are beginning to move out and discriminate," an attitude that could reinfect the military if not checked.

Military people who were deeply involved with race relations when that was a highly visible problem have not been promoted as fast as colleagues in other jobs. Price said in deploring the slackening of interest in equal opportunity efforts.

Aggravating this complacency, Price said, is the dearth of experienced officers who could visibly "keep the faith" by filling top command jobs in the military.

"You're going to look behind me and a few others and find there's nobody qualified to manage" because at the height of the racial crisis in the late 1960s American corporations wooed so many highly qualified blacks out of the military.

"Those left and others didn't come in," Price said. "You've got a void you're not going to be able to cope with in the officer ranks just over the horizon."

The coming shortage, the general said, confronting the military - especially the Army, which is the largest service - will create "a problem of credibility" as the number of black officers in top jobs falls for lack of qualified candidates. "That's where your challenge is coming from."

Price said the West Point example of suddenly finding qualified blacks to appoint to the military academy after years of saying none were available suggests "you've got to makeit happen."