BERLIN -- Once events make their passage from news of the day into history books, it is hard to imagine that they could have happened any other way. They're history, after all. And 20 years later, the fall of the Berlin Wall seems like that kind of history -- a world-changing event that we commemorate and celebrate, its heroes and villains well established, its images and significance clearly comprehended.

But the real story of the wall coming down is a lot less tidy than it may appear in the rear-view mirror. The "decision" to open the border was not a conscious choice at all. Instead of a reassuring victory for the forces of freedom, it was a chaotic and potentially violent mess. One of the most momentous events of the past century was, in fact, an accident, a semicomical and bureaucratic mistake that owes as much to the Western media as to the tides of history.

So what really happened?

In the early days of November 1989, East Germans turned out in massive street protests to demand Gorbachev-style reforms. Their dictatorial rulers tried to appease them by issuing "new" travel regulations. Though the rules suggested that there would be freedom, the fine print still included the national security exemptions that had always prevented East Germans from leaving. None of the people writing these new regulations took the obvious steps that would have been needed to open the border, such as consulting the Soviets or informing the border guards that such a move was coming. In short, there were no signs that authorities intended to open the wall on Nov. 9.

That night at 6, Guenter Schabowski, a member of the East German Politburo who served as its spokesman, was scheduled to hold a news conference. Shortly before it began, he received a piece of paper with an update on the regulations and a suggestion that he mention them publicly. He had not been involved in discussions about the rules and did not have time to read the document carefully before starting.

His hour-long news conference was so tedious that Tom Brokaw, who was there, remembered being "bored." But in the final minutes, an Italian journalist's question about travel spurred Schabowski's memory. He tried to summarize the new regulations but became confused, and his sentences trailed off. "Anyway, today, as far as I know, a decision has been made," he said. "It is a recommendation of the Politburo that has been taken up, that one should from the draft of a travel law, take out a passage. . ."

Among the long-winded clauses, some snippets leapt out: "exit via border crossings" and "possible for every citizen."

Suddenly, every journalist in the room had questions. "When does that go into force?" shouted one. "Immediately?" shouted another. Rattled and mumbling to himself, Schabowski flipped through his papers until he uttered the phrase: "Immediately, right away."

It felt as if "a signal had come from outer space and electrified the room," Brokaw recalled. Some wire journalists rushed out to file reports, but the questions kept coming, among them: "What will happen to the Berlin Wall now?"

Alarmed about what was unfolding, Schabowski concluded with more muddled responses: "The question of travel, of the permeability therefore of the wall from our side, does not yet answer, exclusively, the question of the meaning, of this, let me say it this way, fortified border." Furthermore, "the debate over these questions could be positively influenced if the Federal Republic [of West Germany] and if NATO would commit themselves to and carry out disarmament."

As NATO was unlikely to disarm itself by breakfast, Schabowski clearly did not expect much to happen that night. But it was too late -- by 7:03 p.m., the wires were reporting that the Berlin Wall was open.

Across the border, a West German television channel, ARD, reported the news cautiously in its 8 p.m. broadcast, first asserting only that the wall probably would become "permeable" soon. But for its next news program at 10:30 p.m. -- delayed to 10:42 by a soccer match -- the staff went big. Hanns Friedrichs, the moderator who enjoyed a Cronkite-like status in the country, proclaimed, "This ninth of November is a historic day." East Germany "has announced that, starting immediately, its borders are open to everyone."