South Africa's Botha gaining ground in modern-day 'Boer' war

For almost a year South Africa has witnessed a modern-day Boer war, pitting the government's ''reform'' forces against segments of the white community that would rather hold the line against any encroachment on white privilege.

Standing back from the fray, one can see signs that the battle momentum has swung back to the government and its supporters.

Some of the whites who favor race reform are heartened by this swing - if only because they feel government proposals to allow Coloreds (persons of mixed race descent) and Indians a larger role in government are the most that can be wrung at present from the dominant Afrikaner electorate.

Blacks, who remain at the mercy of apartheid even as the government shifts its policies toward other nonwhites, are for the most part not cheering. But they are paying attention since, at least in the short term, their future remains in the hands of this government.

The plan that caused the split between the government and some of the white Afrikaner community almost a year ago was called ''power sharing.'' The government today is moving toward implementation of that plan for reform (some would say adaptation). Blacks, who are more than 70 percent of the population, will continue to be allowed political rights only in tribal ''homelands.''

Blacks see their exclusion from the power-sharing plan as a government strategy to ''divide and conquer'' nonwhites, and they have opposed the plan from the outset. But the government has apparently been only peripherally concerned with this. Its attention has been focused on wooing Coloreds and Indians to participate, and on driving its right-wing Afrikaner opponents into oblivion.

Prime Minister Pieter Botha can claim victories on both fronts.

The Colored community's Labor Party has decided to go along with the plan for a three-chamber parliament. Labor's decision gives the plan enough credibility for the government to proceed, although the road is apt to be rocky, given mounting opposition within the Colored community at large to the proposal.

In the sphere of white Afrikaner politics, the government is acting with ever-growing self-confidence. There is a distinct change in the tone of its behavior regarding its major right-wing threat: the Conservative Party formed last year by former Cabinet Minister Andries Treurnicht to fight the government's so-called power-sharing proposals.

A veteran member of Parliament says, ''When the Conservative Party broke away , the government did everything to woo them back.'' Now, ''The daggers are out.''

The government is emboldened by events. The Conservative Party and the further-right Herstigte (Reconstituted) National Party recently failed in another attempt to combine their forces in a unified right-wing front. By-elections since the Conservative Party's formation have failed to give them a victory.

Most recently, an important shakeout in the Afrikaans press has given Prime Minister Botha dominance in the Transvaal Province, where the Conservative Party and right-wing influence is strongest. The Beeld newspaper in Johannesburg, which champions Botha's cause, has forced its major competitor - Die Transvaler - to move to Pretoria.

And last week, Minister of Manpower S. P. Botha engaged in some political bravura that seemed telling of the government's mood of confidence.

In heated parliamentary debate, he challenged Conservative leader Treurnicht and another CP member to resign their seats and he would do the same. All three have agreed to resign on Feb. 21.

By-elections in those three constituencies would be seen as the most important tests to date of the National and Conservative strength. All three by-elections would be in Conservative Transvaal constituencies.