Nothing unites white South Africa more than the fear of being overrun in the cities by blacks. But bouncing along the rutted dirt roads of Crossroads, one of the country's largest and most politically explosive black ''squatter'' settlements with a population of some 50,000, many of the fears seem largely unfounded.
Crossroads and the half-dozen other ''squatter'' camps near it also offer evidence that the South African government's policy of strict influx control is springing huge leaks. There are signs the government is recognizing this. The question is whether the government will change the system or simply enforce it more harshly. For now the government seems to be of two minds on that score.
Situated among the sand dunes east of Cape Town, Crossroads is appallingly poor. But once inside the warren of plastic, wood, and metal shacks, one sees a surprisingly well organized, cohesive, and even friendly community. Rather than being a dangerous and unproductive place - as many whites see it - Crossroads appears to be opening up better opportunities for many of its residents. And this is to the long-term good of all of South Africa, many critics of influx control argue.
Robinah Sofute has no doubt her life has improved since she came to Crossroads. She left the Transkei ''homeland'' - about 600 miles away - in 1968 for reasons common to many of her neighbors here: to be with her husband, who worked as a migrant in Cape Town, and to escape the ''homeland'' where she says ''it was very difficult to live.''
Bent over a pan of sizzling fish that will be breakfast for her six children, Mrs. Sofute says life is not so difficult now, even though her husband has passed on.
She and her extended family are doing relatively well because her son operates a thriving auto repair business here.
I met the Sofutes on a brisk winter morning when smoke from outdoor fires was already heavy in Crossroads. Noel Robb of the Black Sash human rights organization had taken me and two American businessmen on a visit to Crossroads.
Rounding a corner, avoiding a vendor doing a brisk business in discounted potatoes, we were flagged down by a black man. We didn't understand Xhosa, but a passer-by gave us a translation: ''Your tire is going flat.''
The businessmen exchanged anxious glances, no doubt wondering how many miles it would be to the nearest gasoline station. Mrs. Robb calmly assured us there was a garage just up the road.
That is where we found Mr. Sofute's business. It was situated in a small clearing surrounded by makeshift dwellings. Already five cars were waiting for repairs.
Mr. Sofute emerged from under the hood of one of the cars in grease-splattered overalls and extended a friendly hand. We explained our problem and in no time the young man was bent over a hand pump filling the tire.
Across the road from the garage is the main school in Crossroads. It is three long rows of multicolored wooden classrooms roofed with corrugated metal. The residents of Crossroads built the school, although it now receives some government assistance.
We peeked into a classroom and a young black teacher spoke with us briefly. She said the class had ''a hundred or so'' pupils. While we spoke, the class stood quietly at attention.
Robb says Crossroads is full of ''entrepreneurs'' like Sofute. Although he has all the necessary certificates to qualify as an auto mechanic, he cannot open a ''legal'' business because he does not have permission to be in this Cape Town area.
The South African government severely restricts the migration of rural blacks into the ''white'' cities through stringent influx control measures. Only blacks needed for labor are allowed in. Those caught here in the Cape Town area without permission are given a choice of 70 days in jail or a fine of about $50.
Influx control allows whites to retain control of the urban areas and helps keep as many blacks as possible in the tribal ''homelands'' set aside for blacks. The policy bites extra hard in the Cape Town region because the government stipulates that jobs in this area should go first to the indigenous Colored (persons of mixed race descent) population.
Still, the government admits up to 100,000 blacks are living in the Cape Town area ''illegally.''
Crossroads was one of the largest squatter camps thrown up by blacks. Its residents include both blacks legally entitled to be in the Cape Town area, but for whom the government has provided no housing, and blacks who do not have permission to be in the region.
By special exemption, the government allowed Crossroads to stay in 1979. But the government has continued to come down hard on other squatter settlements.
The harshest side of influx control has been on display here in recent weeks as government officials have raided squatter camps, tearing down the flimsy shelters of destitute black families, only to find the shelters erected again the next day.
But even as the government rigidly enforces influx control, some of its own officials have attacked the policy. J. Gunter, director of the Western Cape Development Board - the agency charged with administering influx control here - recently told a Cape Town newspaper: ''We now have proof that prosecutions are failing to stop the illegal influx and it is clearly impossible to try to stop the urbanization process here.''
It is extremely rare for lower-level officials in South Africa to criticize government policy. Some political analysts say Mr. Gunter's comments are a clear signal that some officials much higher up in the government are calling for a review of influx control, at least in the Cape Province.
Legislation to tighten influx control was postponed this year and will be taken up by next year's Parliament. But that Parliament will include Coloreds and Indian members whose presence, although not decisive, could encourage a new approach to influx control, political analysts predict.
The ultimate plan for dealing with blacks in the Cape Town region is to move all those ''legally'' in the area to a new development called Khayalitsha. It is about 25 miles from the center of Cape Town - farther out than existing townships - among sand dunes bordered on one side by the sea and on the other three sides by a military base.
In Khayalitsha the government is providing new residents with two-room cinder block houses, with water points and no electricity.
Black resistance to moving to Khayalitsha (it means ''new home'') is building , although some 200 families have moved there. Some object to its distance from Cape Town and the high cost of commuting to work. Others say moving will break up the community cohesiveness now enjoyed in established townships. And many suggest that ''illegal'' blacks will be ferreted out in the process and probably evicted from the Cape Town area.
Robb says Khayalitsha is attractive to some blacks simply because it offers better housing. But she says for the development to gain acceptance the government must not force blacks to move there, but allow them to move by choice.
Mrs. Sofute is adamant: ''I will never move there.''