Pretoria Letter/Joe Humphreys: We weren't a wet weekend in Pretoria before we had committed our first security faux pas. A midday stroll in a pretty city centre park bustling with young families hadn't seemed like a risky pursuit - until we met up afterwards with some nativised expatriates.
"You didn't go there?" we were asked incredulously. "That park is a no-go area!"
Sure enough, I read in a newspaper article the next day that - among other things - the said park had become a "den" of prostitution, and associated criminality.
The episode taught us something about the value of local knowledge in a new environment. But, perhaps more so, it taught us about the fluid nature of security in South Africa.
Before moving here we had hoped - and half-expected - that the country's crime problem had been over-hyped. In fact, crime is a big problem in South Africa, especially in the cities.
The latest horror story to jolt the nation has been the murder of a judge's four-year-old granddaughter during a house burglary in which the girl's nanny was gang-raped.
Police incompetence surrounding the case (the girl was first reported kidnapped but then discovered more than a day later under a bed in the home) has added to the sense of unease.
A critical aspect of the case is that both the victims and the alleged perpetrators of the crime were black. It wasn't surprising - as blacks are the chief victims of violent crime in South Africa - but it has jolted some members of the political establishment who had come to see crime as a "white-only concern" into rethinking their views.
The chairman of the South African Human Rights Commission, Jody Kollapen, identified the issue at stake when she wrote in a recent newspaper article: "One can hardly talk of advancing a human rights culture of respect, tolerance and understanding and of a commitment to equality when crime poses such a huge physical and psychological threat to the existence of so many."
The corrosive influence of this threat can be seen not just in society but in individuals, who have started to retreat into cocoons of their own making.
Increasingly, whites are fleeing to gated communities, like Waterlake Farm, the latest "secure estate" to spring up outside Pretoria.
Using the slogan "Out of Harm's Way", a brochure for the development promised "the kind of peace of mind that only generations before us had experienced". This paradise was illustrated by children fishing and adults lolling about in the sun. (Note, however, not one of the 25 models appearing in the brochure was black.)
Of course, one doesn't need to leave the city to witness, or experience, South Africa's fortress mentality. In the better-off suburbs, no house is complete without electric fencing, an elaborate alarm with armed response back-up, and perhaps a guard dog or two.
It is not uncommon for people to lock themselves in their bedrooms at night - naturally with a panic button on the bedside locker. And the most familiar sound of morn is the clanking of Trellidor, a lattice of collapsible bars covering almost every porch in suburbia.
Are the risks so great to justify such paranoia? Yes, sighs virtually everyone you meet. And yet you have to wonder.
How much of this anxiety is a hangover from the apartheid era, when the white ruling class drummed up fears of mayhem and mass murder if and when power changed hands? Some whites have conceded an element of neurosis in their make-up, and at least one of them has put a name on it.
Greg Potterton, managing director of a Cape Town-based trend-spotting company, has coined the phrase "Fear of the Outside World" (Fow) to describe the mindset. He told this reporter that while everyone experiences irrational fears, "it's amplified in South Africa because of the phenomenon of urban crime. For a lot of South Africans, this fear is entrenched in their lives and they don't even realise it."
Fow, in his view, can be seen in everything from the locations in which South Africans live - "sanctuaries for themselves and their loved one" - to the decor in which they find comfort. "People are scared of adventure, even in superficial areas like fashion-wear," he claims.
For a new arrival like myself, this is somewhat disconcerting - if only because the gap between prudence and paranoia is unclear. Is it prudent, for example, to keep my windows rolled up at traffic lights, or paranoid? (Either way, it is damn near impossible in the stifling city heat!) It is also disconcerting to think of South Africa as a frightened nation, especially given its history. The collapse of the apartheid regime was often described as "the triumph of hope over fear".
What now for the Rainbow Nation if fear is all-pervasive?