If you've ever tried to hold out for one direction when all your friends were headed the other way, you can sympathize with the Rev. Leon Sullivan.

You can also understand the mental anguish he must have gone through before he finally yielded last week to the superior numbers, if not necessarily the superior judgment, of his friends.

Leon Sullivan has abandoned the fair-employment principles he promulgated for U.S. firms doing business in South Africa and joined those who call for total disinvestment.

The stated reason for his turnaround was that the Sullivan Principles had failed to end apartheid. But if it had been your teen-age son rather than this 64-year-old minister, educator and civil rights activist, you might have called it by its right name: peer pressure.

Sullivan's formulation of his six-point code some 10 years ago immediately made him one of the key American players in the anti-apartheid drama. The principles called on U.S. firms to defy South African law by integrating all company facilities, establishing fair employment practices and equal pay, developing training programs for nonwhites, increasing the number of blacks in managerial positions and, later, by lobbying against apartheid.

By last year, according to a report prepared by the consulting firm of Arthur D. Little, Inc., the 179 companies that endorsed the code were spending more than $33 million a year on education, housing, community development, legal assistance and other programs for South African blacks, while also purchasing more than $9 million worth of goods and services from nonwhite businesses.

But in recent years, the principal push by American activists has been to force U.S. companies out of South Africa altogether. Sullivan found himself in the uncomfortable position of working to make apartheid less oppressive while his civil rights colleagues, college students and other activists were pushing for a complete economic and diplomatic break with the white regime. Last year, he announced that unless apartheid was toppled, he would call for "a total embargo." He did so last week, acknowledging that his milder approach hadn't ended apartheid.

Of course it didn't. U.S. firms never employed more than about 120,000 South Africans. American companies employed only about 2.3 percent of the white work force and less than 1 percent of black workers. The impact of the Sullivan Principles, as their author must have understood, would be only at the margins: by setting an example of fairness that South African firms might follow. They were not expected to end apartheid, whose key features include official segregation and the absolute denial of the franchise to blacks.

But if it should have been clear that the Sullivan Principles wouldn't end apartheid, it should also be clear that disinvestment won't end it either.

The economic recession, created in large measure by the combination of disinvestment and sanctions-induced credit problems, is hurting the South African economy. But disinvestment is also allowing South African whites to acquire abandoned companies at bargain-basement rates and without the necessity of adhering to Sullivan's costly principles. According to the State Department, "To our knowledge, not one of the South African companies left has continued the fair labor standards and social programs of the Sullivan Code."

Moreover, the smaller the U.S. economic and diplomatic presence in South Africa, the less the American influence there.

Alan Keyes, assistant secretary for international organization affairs and the highest ranking black in the State Department, says flatly that the combination of sanctions and disinvestment has been counterproductive.

"By destroying the nonviolent means of struggle against apartheid and encouraging violence, the hopeless view becomes a self-fulfilling prophecy {to which} the media in this country contributes. . . . America is well down the dead-end road of irrelevance to any process of relatively peaceful, democratic reform in South Africa."

Keyes challenges such pro-disinvestment advocates as Jesse Jackson and TransAfrica's Randall Robinson "to debate the merits of this question based upon the facts, and let the American people be the judge."

It's a debate I'd like to hear. "Disinvestment is . . . allowing South African whites to acquire abandoned companies at bargain-basement rates."