More than a year after the killing and burning began in South Africa's black townships, the backlash that is now hitting the economy has jolted the ruling white minority at last into realizing that their country is in crisis.

Yet the power structure in South Africa is such that the wave of anxiety now gripping many whites -- that has galvanized the business community into a rare intervention in politics -- is being translated into political action only with difficulty.

After 37 years in power, the ruling National Party has become a sluggish giant headed by an aging leader who seems unable to come up with new ideas for dealing with the crisis and has no obvious successor offering better hope for the future.

The party acknowledges the need to dismantle the apartheid system it constructed, but like many of the world's aging communist parties, it is too ossified and too much the prisoner of past ideology to devise and implement a credible alternative.

Yet it is assured of remaining in power, kept there by the ethnic loyalty of the Dutch-descended Afrikaners who constitute 60 percent of the controlling white minority.

The party's lost vitality was apparent at a congress of its powerful Transvaal branch in Pretoria yesterday. It was a zestless gathering for a political movement that once throbbed with the populist passions of the underdog Afrikaners as they struggled to gain control of the country from the capitalist Britons who had defeated them in the Boer War of 1899-1902.

There was none of the old hoopla with flags and bunting and wild applause for the folk heroes who were the party leaders. The speeches were dry, and the applause was dutifully polite.

Only a few thin voices joined in the once rousing sing-alongs of patriotic folk songs, and the dark suits of the delegates and the rows of Mercedes and BMWs parked outside bespoke their new status as a staid and entrenched establishment.

President Pieter W. Botha's keynote address offered no new insights into the country's worsening domestic and international situation, except to warn party followers to be on their guard against an "onslaught of disinformation" designed to sow "pessimism and defeatism," and to stand together against the "forces of darkness" threatening to seize control of the Afrikaners' country and swamp their culture.

When a solitary member of Parliament of mildly liberal inclination ventured the only criticism of the day with a cautiously phrased suggestion that perhaps the tough police crackdown in the townships had become an end in itself, that maybe black leaders who were being arrested should be drawn into negotiations instead, and that the right to protest seemed to be getting brushed aside, he was rebuked smartly by the president.

"Let me tell you this," Botha admonished the legislator, Wynand Malan. "This government is not dictatorial, but it will not tolerate protests that take place under the red flag and lead to stoning attacks on policemen."

Faced with this failure by the country's rulers to respond to the deepening racial conflict, an attempt to mobilize support outside the government for the holding of a national convention of all races to write a new constitution for the country was launched in Johannesburg today.

The initiative came from the small opposition Progressive Federal Party, which has called for the formation of a "convention alliance."

The liberal Progressive Federalists have the support of about one-fifth of the white electorate, mainly among persons of British and Jewish origin who make up 40 percent of the white population and play a dominant role in the country's business sector.

This gives the PFP only 27 seats in Parliament to the National Party's 127, yet it is the only rallying point for those whites who seek to pressure the government or dissociate themselves from its policies.

More than 150 top businessmen, church leaders, lawyers and a sprinkling of blacks -- notably from Zulu Chief Gatsha Buthelezi's Inkatha movement -- attended today's meeting to launch the convention alliance, and afterward, a 30-member steering committee was set up, headed by Jules Browde, a leading lawyer who is chairman of the Lawyers for Human Rights organization.

The alliance meeting has aroused a good deal of interest among the worried business community, but so securely is power locked in to the National Party that few political analysts here hold out much hope of it making a significant impact.

Business in its own right has far less political influence than in the United States. Its association with the British-descended minority makes it part of the traditional opposition to the Afrikaner nationalist government and therefore an outsider.

There is a tacit alliance between the political and business establishments, and President Botha has tried to court the businessmen during his eight years in office. They lack the direct leverage that business has in other capitalist societies, however, and their attempts at intervention are rare.

Business leaders spoke out for reform after the police killings of 69 black passive resisters that shook the economy in 1960, and again when there was prolonged racial unrest in 1976. But for the most part they have avoided involvement in political controversies, preferring to keep in the government's good graces.

Some people think that the calls coming from business this time are more serious and that the government will find it harder to ignore them. This is partly because, although Afrikaners remain a minority in the business sector, their numbers have increased considerably during the past decade, and Botha has sought to identify the party with this emerging Afrikaner capitalist class.

In the light of this it is seen as particularly significant that Anton Rupert, the doyen of Afrikaner businessmen who heads the transnational Rembrandt tobacco corporation, also has called for hastened change.

The recent meeting between a group of businessmen, headed by Gavin Relly, chairman of the giant Anglo-American Corp. mining company, to meet exiled leaders of the outlawed African National Congress in Zambia, is seen as another significant new initiative taken by the business sector.

Although no substantive negotiations took place at what was described as a "getting-to-know-you" meeting, it helped demythologize a bogeyman image of the ANC that the government has propagated since it banned the black nationalist movement 25 years ago and prohibited the South African media from quoting any of its leaders.

This could make it easier for a future meeting to take place between South Africa's antagonistic Afrikaner and black nationalists, which some observers believe is essential if there is to be any hope of a peaceful settlement between the races.

Zac de Beer, executive director of Anglo-American who was at the meeting in Zambia two weeks ago, said he believes it also indicated that the ANC is more willing to negotiate with white South Africans than most people here realize.

"Although we don't see it that way, the ANC's view is that big business is part of South Africa's ruling establishment, which means that if they are willing to talk to us, they cannot be far from being willing to talk to the government, too," de Beer said in an interview yesterday.

Despite these new factors, Hermann Giliomee, a respected political scientist, remains skeptical about the importance of business' new political activity.

"Business tends to speak up only in times of crisis," Giliomee said. "When the crisis passes, they lose interest again. They have no clear strategy, no clear alternative and no clear leadership. . . ."

Giliomee may be right. There was no evidence at the National Party congress yesterday that the agitation by the businessmen was making any impression on the delegates.

The concern of the business community was the continuing decline of the rand currency, which plunged again yesterday to 37 U.S. cents. This is only two cents above what it was when the government tried to bolster it by declaring a freeze on repaying the principal on foreign debts last month. But the chief concern of the 600 congress delegates was the maintenance of political power. They are an ethnic oligarchy that is aware that granting political rights to the black majority except under the most carefully circumscribed conditions will lead to losing control forever.

How to meet the black clamor for change without ultimately bringing about their own political extinction is the Afrikaner nationalists' dilemma.

For a time President Botha seemed to have the answer: a steady extension of power to the black, mixed-race and Asian groups to run their own affairs, while giving them a token role in decision-making on "general" affairs in a carefully structured system where ultimate control would remain in National Party hands.

At the same time Botha embarked on a piecemeal dismantling of the purely segregationist features of apartheid.

But instead of placating the blacks as Botha expected, the reforms have uncorked years of bottled-up anger and a demand for an end to minority rule, setting the black townships aflame.

Botha said yesterday that he would announce the next phase in the reform program at another provincial congress of the party to be held Sept. 30. In the meantime, he repeated that it was out of the question to give blacks an equal vote with whites, or to give them a separate parliamentary chamber like those already established for the mixed-race and Asian minorities. He was prepared to negotiate for something other than that with "responsible" black leaders who were prepared to denounce violence -- if only they would come forward.

It is difficult to know whom Botha has in mind for such negotiations. He already talks regularly with the leaders of the tribal "homelands" and the township councils established under the apartheid system, but they are largely discredited within their own communities and have no influence over the young radicals who are stirring things up in the townships.

The only people who can assert influence over the radicals would seem to be the leaders of the ANC, with whom Botha refuses to deal, and of the United Democratic Front, whom his government has either detained or charged with treason or subversion.

The leaders of hundreds of community organizations affiliated with the United Democratic Front are likewise under arrest. The only major UDF figure still untouched by the police crackdown is Bishop Desmond Tutu, but when he sought a meeting with Botha recently, the president brushed him aside.

That leaves only Chief Buthelezi, a resolute government opponent among the otherwise acquiescent homeland leaders. But even if the government succeeds in luring Buthelezi into negotiations, his authority is largely confined to the Zulu tribe of Natal Province.

Conversations with party congress delegates threw little light on the government's intentions. Several made the improbable suggestion that if the security forces could stamp out "intimidation," the township councilors might emerge as credible leaders.

"I don't think they the government really have a model for negotiation in mind at this stage, but I'm sure they're working on it," one delegate said.

Pressed on the point, the delegate agreed that only the ANC leadership had sufficient influence over the radicals to end the violence in the townships. "We will have to meet with them at some stage, but they will have to drop their commitment to violence first," he said.

Could Botha ever engage in meaningful negotiations with the ANC? That would be difficult, the delegate admitted. He said he thought that it might have to wait until Botha, who is 69, decides to retire.