A CITY IN CRISIS : A Few Hours When Our Town Hung in the Balance : City’s two worlds collide as the riots reach out and grab white Los Angeles.

No one has bothered to talk much about those few hours of mid-afternoon on Thursday, that brief period when Los Angeles hung in the balance. But those hours may leave the most indelible mark of all. They were the hours when the invisible borders of the city were breached, and nothing seemed capable of stopping the riot. When Hollywood Boulevard began to burn, when Beverly Hills and Hancock Park seemed ready to go next.

Let me put it another way: Those were the hours when the nether world reached out and grabbed hold of white Los Angeles. In doing so, this insurrection announced its primary distinction from the Watts riots of 1965. It would not stay caged in South-Central. This riot would leap northward and, in so doing, end forever the belief that white Los Angeles can successfully insulate itself from the burgeoning hordes of the nether world.

As it happened, I spent an hour of that afternoon shopping for dinner in a Hughes market on Coldwater. This market might serve as a perfect slice of white Los Angeles. At the Coldwater Hughes you get your burghers from Sherman Oaks, your occasional demi-celebrity, your young couples with two incomes and a baby.

By 3 p.m., this constituency had gotten the message of the riot, loud and clear. Hundreds of them jammed the aisles of Hughes as if it were the day before Thanksgiving, filling two carts at a time. They fought over roasting chickens, in short supply. Some of them laughed at the mayhem and their own unseemly need to empty the shelves before the rampagers arrived and torched the joint. Others failed to see the joke.

Surprisingly, in the checkout lines, everyone wanted to talk. Normally, at Hughes, talking in the line is regarded as bad form. But now the war had come, or something like war, and the rules were suspended.

Halfway through the line, a woman tapped me on the shoulder. She wondered if I had heard any late news from Beverly Hills. Her husband worked in Beverly Hills. She had tried to call but the lines were jammed.

Beside her stood a perfect, blond California child. A girl, about 5, shy, using one finger to play with her teeth. I told them Beverly Center had closed after some sort of attack. A few scattered assaults had been reported on side streets. All in all, I said, small stuff.

Then, in a mistake, I added that my information was an hour old. The mother instantly projected forward from my description and saw Beverly Hills in flames. She knew how fast the riot was moving. And I, having inspired her worst nightmare, could not assure her that it was wrong.

She patted her daughter on the head and finally turned to the person behind her in the shopping line. “Do you know anything about Beverly Hills?” she asked. Then, realizing the ambiguity of the question, she clarified.

“Has Beverly Hills fallen?”

Beverly Hills had not fallen. We know that now. But during those few hours of mid-afternoon on Thursday, the idea that primary sections of the city might “fall” to the enemy did not seem unreasonable. If you were paying attention, you knew that the police and sheriff’s deputies had lost all control over the riot. No effective resistance was being mounted. The whole core of Los Angeles, from downtown to Santa Monica, stood open to the advancing fires.

Those hours, I think, have changed the way we see the city. For many years, Los Angeles, like most American cities, has contained two worlds that operate like parallel universes. Each one steams along, hardly aware of the other. The world of money and jobs and scrubbed faces fills one universe. The nether world fills the other.

I say “nether world” because it contains a complex crowd of blacks and Latinos and some Koreans and Vietnamese and Samoans and whites. Among them are good people and bad people, just like the other world, except this crowd has been more or less excluded from the economic life of the country. They are much studied and worried over, and every year their numbers grow.

But, for the most part, we of the first world in Los Angeles have kept them contained. The nether world stayed south of Wilshire and east of Highland. You could live in Laurel Canyon, drive every day to an office in Westwood or Century City, and never come close to the nether world.

That separation of the worlds makes Los Angeles different--a little different--from other cities. In New York or Washington, the separations tend to be expressed in blocks rather than miles. People in either world can feel the proximity of the other.

Here, the sheer distance of the separation makes each world seem unreal to the other. And to the white world, it lends an air of security. If you live west of Highland and north of Wilshire, you’ll be OK. You’ve put a lot of turf between you and them.

As I said before, even the 1965 riots obeyed this rule. The nether world never moved north of Pico. But last week, the two worlds suddenly came face to face.

Late Thursday afternoon, I remember turning on the television and watching a young couple from Hancock Park. They stood next to Samy’s camera store on Beverly at La Brea, which is close to Hancock Park, as it burned furiously. The woman expressed her anger and disbelief. She wore sunglasses and an expensive, white T-shirt, the uniform of the young and moneyed.

Where were the cops, she wanted to know. Where were the people paid to protect the city. The looters were everywhere, sneaking down the alleys, driving up the streets, crawling through the windows.

“They’re coming in like ants,” she said.

I tell her story only to suggest it will be a long while before she--or others--can restore their old feelings about the quiet streets of Hancock Park. They now know that their neighborhood is within reach. In some subtle way, the rules have changed.

I wonder about the reaction, once all this sinks in. Do Hancock Park and the other neighborhoods become tainted because the looters came so close? Do the truly removed places, like Pacific Palisades, start to look like the last safe havens? Will the white people run, as they always have before?

We’ll see. Just as we’ll see whether this riot comes and goes, an isolated event in a sea of relative calm, or whether we have just witnessed the beginning of something long and ugly.

What we do know is this: Los Angeles came closer to falling than our leaders would like to admit. It came down to the question of whether the Humvees would arrive in time. If they had delayed eight more hours, it might have been too late.

Of course, the Humvees did arrive in time. The cavalry came. But people don’t forget that feeling. They don’t forget begging strangers for information because their husbands or wives may be caught in the collapse of their world. And they will never feel quite the same about their city.

Late on Thursday night, I drove back to Hancock Park. I wanted to see if it had gone vigilante. Sure enough, it had. Along the commercial district of Larchmont Boulevard, a huddled crowd of merchants waited out the night.

We sat together under the eaves of an interior decorator’s store. Across the street was the wine shop. Normally, these men operated these stores, or ones just like them, up and down the “village.” Tonight, every one of them, with the exception of the newsstand owner, carried a gun.

After some minutes of waiting, we suddenly went tense. A 20-year-old pink Cadillac with loose fenders and a missing headlight had turned a corner and headed down Larchmont. Inside the car, sitting low, four men could be seen. Slowly, the Cadillac rumbled toward our group, and stares were exchanged as they passed. The Cadillac kept going.

But then, three blocks down, it stopped and turned around. The Cadillac was coming back.

We crouched down behind car fenders. One of the merchants, appreciating the ironic turn of life on Larchmont Boulevard, uttered one soft phrase.

“Lock and load.”

We crouched lower still. Every pistol was cocked. And there we waited, in the dark, for the pink Cadillac and all it meant.

As it turned out, the Cadillac contained friends, not enemies. The merchants stood up and shook hands. But everyone had a certain look. They, too, had gone through something that would be hard to forget. A night when the business of distinguishing friend from enemy became very important. And the consequences infinitely dangerous.