THE YEAR IS 1997--a hot, dry morning in mid-September. In Kasumigaseki, bank clerks with their ties knotted too tightly scroll down lists of figures before their first meetings of the day. In Higashi-Ginza, sales assistants flick dusters around their glitzy boutiques. In Hibiya Park, mothers with toddlers in pushchairs stroll over to inspect the carp pond.

Death comes suddenly, out of cloudless skies. The Soviet-made Mil 17 helicopter thunders across Tokyo's political and economic axis--from the Imperial Palace to Akasaka--dropping canisters of liquid nerve agent which explode on the ground and vaporize instantly into lethal sarin gas. People stumble in blind terror from buildings, choking and vomiting. Those inside are not spared, as a lethal strain of botulism in the water supply begins to take its toll. Soon, corpses clutter the streets and sirens slice the poisoned air.

Total chaos reigns in the Diet Building, where Prime Minister Ryutaro Hashimoto attempts to convene a crisis Cabinet meeting amid fresh reports of an unauthorized scramble by the Self Defense Force's elite First Airborne Division. Before the meeting can begin, gas-masked mercenaries armed with AK47s burst into the room to deliver an ultimatum: unless the government surrenders power to the supreme leader of a little-known religious sect, the group will launch a devastating nationwide offensive using more nerve gas--plus nuclear, biological and conventional weapons.

Meanwhile, the nation's airwaves have been hijacked by microwave transmitters. Every TV network is showing the same picture--of a wildly bearded man, smiling beatifically, eyes slitted with purblind bliss. A voice-over intones the mantra: "People of Japan, the time has come. Long live His Holiness the Master Shoko Asahara! Long live the Kingdom of Aum!" The face disappears, and the screen changes to a live shot of Mt. Fuji, its snow-capped peak shimmering in the sun. Then the camera shudders as a mammoth explosion rips through the earth and, unthinkably, a giant mushroom cloud rises above Fuji's shattered slopes. . . .

ALL RIGHT, CUT. OUR fast-forward scenario is getting out of hand. The vision of Aum Shinrikyo seizing power in a lightning strike at the heart of Tokyo . . . well, it's too surreal, too nonsensical, a reckless ballooning of fact into science fiction. Or is it?

For anyone who has experienced Tokyo life over the last four months, or followed the chilling confessions of arrested Aum followers, the unimaginable is something that now arrives every morning along with the Daily Yomiuri.

Who, just over a year ago, could imagine the slaying of 19 people and the injuring of nearly 6,000 in two sarin attacks? Of the near assassination of the nation's top cop by a masked assailant who escapes by bicycle? Of our city grinding to a standstill on April 15 because a pajama-clad nihilist predicted "a horrible disaster"? Of bags of chemicals found in Shinjuku Station only minutes before they might have combined to form a hydrocyanic gas that could have killed thousands? As Aum's terror tactics escalated, perceptions shifted: appalled surprise that such crimes could be perpetrated changed into grim forebodings of worse to come.

With the arrest and indictment of Shoko Asahara and his key minions on charges of murder, our immediate fears subsided. But fed on a daily media diet of gruesome revelations based on police leaks, we all remain under Aum's captivating spell. This week's helping includes reports that the sect was trying to build "plasma" weapons that destroy living organisms but keep buildings intact; that one follower was brutally strangled to death in front of Asahara on his orders; and that opponents' corpses were disposed of in a giant home-made microwave oven.

At first these bizarre discoveries seemed the random spoils of religiously-inspired madness. But soon it emerged that this cash-rich but morally bankrupt sect was working towards a more strategic Grand Plan--nothing less than a coup d'etat to usher in the Millennium of Aum. And, we're led to believe, if they hadn't fallen victim to their own paranoia and hubris--thereby launching the Kariya abduction and the Tokyo attack which led to their demise--they would have had the motivation, the means and the momentum to succeed.

Yet do all these revelations really equal the sum of their parts? The exaggerated "what if?" scenario above has a serious purpose: to understand how close Aum got to fulfilling its guru's apocalyptic vision, and to highlight how our lives have been changed in the aftermath of their attempt. Let's rewind--back to the time when Aum Shinrikyo's aim shifted from bringing enlightenment to the world, to casting it into eternal darkness.

THE KEY TO Aum's purpose, of course, is Shoko Asahara himself, the former peddler of quack medicines who became the self-proclaimed prophet of the future. The hunger for power was there as early as childhood, when the partially sighted Asahara would bully and charm his sightless classmates at a school for the blind. But a crucial turning point came in 1990, when Asahara and 24 acolytes stood as candidates in the Lower House elections.

If anyone then was aware of Aum at all, it was as chief suspect in the disappearance of lawyer Tsutsumi Sakamoto and his family the year before. Now campaigning for public office in Shiva elephant heads and papier maché Asahara masks, Aum members were ridiculed by media and public alike. The jokes seemed warranted: the cult candidates won only 1,782 votes--not even enough to account for its own membership.

In retrospect, we forgot about Asahara with fatal swiftness. For it was Asahara's dismal failure to gain power by legitimate means that apparently provided his motivation to try other, more sinister ways to extend his dominion. "He was deeply disappointed by the result," says writer Shoko Egawa, who has covered the sect from its early days. "Afterwards, he flounced off in disgust to the island of Ishigakijima and worked his followers into a frenzy with predictions that Mt. Fuji would explode."

The election campaign was pretty much the last Tokyo saw or heard of Asahara and his followers--or, it seems, wanted to. Aum went underground and out of town. More crucially, it went unchecked. The Sakamoto disappearance prompted the largest manhunt in Japanese history yet had failed to pin any crime on Aum. As it turns out, the sect was committing crimes from the very beginning, including land fraud, extortion and kidnapping. But the police didn't interfere--a guilty reaction, perhaps, to a fascist era when religions were ruthlessly persecuted--and other authorities didn't have time to care. There are 6400 religions registered at Tokyo City Hall, and only four staff monitoring them.

Meanwhile, the guru's expanding ego was going supernova. He was calling himself "tomorrow's Christ" and "this century's savior." He was predicting a "final war" in 1997, when invading American forces would kill nine out of ten people and lay waste to 20th-century civilization with biochemical and nuclear weapons. And he was hell-bent on developing the means to nudge his apocalyptic prophesies toward fruition.

If police reports are correct, the confessions of arrested members show that the sect was allowed to build up a devastating armory. Dummy companies bulk-bought chemicals and delivered them to the mammoth "satian" facilities at Kamikuishiki--with no check by the authorities. There, Aum's scientists spent Y3 billion in an attempt to produce enough sarin and other nerve agents to murder millions. With Asahara's blessing, the first "test run"--June 27 in Matsumoto--killed seven.

Using the skills of Seiichi Endo, a former researcher at Kyoto University's Viral Research Dept., the cult reportedly used horse blood in unsuccessful attempts to produce a serum that causes acute food poisoning; they tried to cultivate highly toxic anaerobic bacteria such as botulinus; and a sect medical team went to Zaire in 1992 to investigate a big disease with a little name--Ebola.

One turning point in the arming of Aum was the opening of its Moscow office in 1992. Russia, in the first flush of its post-Communist free-for-all, provided a huge new source of readily available firepower. Kiyohide Hayakawa, the commander of Aum's military operations, allegedly made frequent arms-buying trips to the bargain-basement remains of the Soviet Empire. "Second-hand T-72 tank priced at $200,000 to $300,000," his notes read, "AK47 rifle, $1,000," "200 troops OK." The notes also ponder the imponderable: "How much do nuclear warheads cost?" It is still unclear how close Aum came to acquiring a nuclear device, but their eagerness to do so seems obvious. Last December, followers broke into Mitsubishi Heavy Industries, a major contractor for military equipment, to steal data on a state-of-the-art laser method to enrich uranium.

While the brains developed the arsenal, other members provided the brawn. Osaka day-laborers were recruited and trained on the pretext of filming movies. The cult's "commando unit" trained daily from 8am to midnight on Mt. Fuji's slopes, perfecting Chinese-style physical exercises using qi energy, body-building and martial arts; judo was taught by Asahara, a second dan. Said a former follower: "Their minds were so fixed I felt certain the cult was preparing for war."

Aum also eyed another source of ready-trained troops: the nation's own 250,000-strong Self Defense Forces. Under the direction of Yoshihiro Inoue, the wily "minister of intelligence," the sect reportedly recruited over 58 members or ex-members of the SDF's ground, airborne and maritime divisions. One SDF officer was drugged and driven to Kamikuishiki, where Asahara repeatedly urged him to join. One devotee in the SDF's First Airborne Brigade--which, as the nation's most combat-ready unit, would defend Tokyo in the event of a coup--bugged his commander's phone in what was apparently part of a blackmail plot to take control of the elite brigade. Asahara's SDF followers also provided a flow of classified information on the nation's aircraft, personnel and missiles.

In the space of a few years, Aum changed from a bunch of yoga enthusiasts on an esoteric quest to a sophisticated squadron of intellectuals with the power to wreak havoc in Tokyo. While most of us remained in ignorant bliss, legal battles were being won and lost across the nation, and bitter complaints voiced--not least by Kamikuishiki's villagers, whose protests against the cult's invasion in 1992 went largely unreported by a Tokyo-focused media. The police were equally uninterested. "Before the [satian] raids, the police thought we were the nuisance, not Aum," one villager said.

And so, unhampered by official interference, the sect's momentum grew. By last summer, it had set up the shadow government poised to take over post-apocalypse Tokyo. Shoko Asahara reportedly warned a cult doctor that war might start as early as August 1994. "Casualties are expected, you must be prepared," the guru said. By the time Tokyo next heard the words "Aum Shinrikyo," the cult was set inexorably on course for the "final war" its guru so desperately craved.

AUM WENT A LONG way in preparing for all-out war with the state. But by the beginning of this year, a new obstacle blocked its plans for global domination: itself. The number of desertions and kidnappings were evidence that the momentum the cult had built up was in danger of tearing it apart.

And despite recruiting some of the nation's best and brightest scientists, Aum was still far from perfecting an arsenal capable of incapacitating Tokyo. Though sarin was produced, Professor Kei'ichi Tsuneishi of Kanagawa University, a science and warfare expert, believes Aum did not have the capability to develop effective biological weapons. To allow bacteria such as the lethal botulinus to survive exposure to the air, Aum's scientists would need to make recombinant DNA in order to change the bacteria's gene structure. "From talking to members of Aum's science team, I realized that they did not have knowledge of recombinant DNA, although they had been trying to discover it for two or three years," says Tsuneishi.

If Aum had managed to recruit a follower with the relevant training--and the recombinant DNA technique is taught at only a few institutions--the cultivation of a lethal form of botulinus would be easily conceivable. "A prefabricated building like Aum was using would have been adequate," says Tsuneishi.

Even so, Tsuneishi dismisses the scare scenario of poisoning Tokyo's water. "Water systems contain a great deal of chloride and other chemicals that would kill or weaken the bacteria," he says. "With a strong type of botulinus such as the dysentery gene, a terrorist could fatally poison all the customers at a restaurant, but not wipe out an entire city in one fell swoop."

For Mitsuo Takai, a former head of an SDF training school and force member for 36 years, a deadly air attack by sarin is far more plausible. He sits in a Shibuya coffee shop, casually scribbling out possible strategies that Aum might have used to wipe out central Tokyo (adding that he was careful not to mention any of this during his recent guest appearances on TV, in case he gave anyone the wrong ideas.) "The Tokyo subway attack could have been much more devastating," he says. "If Aum had used an effective dispersal system, such as a vaporizer, there could have been many thousands dead."

Aum supposedly could have produced 50 tons of sarin--enough to kill a staggering 300 million people. Takai says only one or two tons would be sufficient to slaughter half the people in an area of two square kilometers. "If this amount was dropped over Kasumigaseki, Akasaka, Yotsuya and around the Imperial Palace and spread with dry ice," he says, "the numbers killed would be far higher than those of the Kobe earthquake. Dead bodies would be littered everywhere and there would be total panic. It would take more than one hour for the SDF to reach the scene."

But Takai stresses that "the gas would have to be of a very high quality"--and the chemical cocktails Aum scientists mixed were not. He adds that Aum did not have the hardware to kill effectively--that is, to spread gases by air. The sect-owned Mil 17 chopper had a capacity to carry four tons, but it didn't appear to be working. Aum also bought two remote-controlled crop dusting helicopters, which reportedly crashed on their first test run.

Could links with the military have provided them with the necessary aircraft? In total, nine SDF members have now been arrested for involvement in illegal sect activities, including the firebombing of Aum's Aoyama HQ. Perhaps predictably for a former SDF trainer, Takai plays down the threat that Aum's infiltration of the armed forces could have posed to national security. "Only 50 or 60 SDF members were involved, none of them high-ranking," he says.

Takai admits that the recent revelations have jolted the SDF brass out of its complacency. The armed forces, for instance, has never undertaken drills to cope with a paramilitary attack on the Diet or Imperial Palace. "We have never trained for such events because they seemed so unlikely," he says, adding that responsibility for domestic crises has rested firmly with the police force. "Perhaps now we've had this sarin attack, we will have to start thinking about such eventualities."

Military journalist Hisayoshi Tsuge already has. He believes the Diet is chronically vulnerable, and has just written a novel explaining why. In The Coup, Tsuge paints a scenario of 120 terrorist guerrillas armed with AK47s invading the building. The Diet's four main gates, he says, are each guarded by only a couple of sentries armed with pistols. "Thirty guerrillas at each gate could easily overpower the guards. There would be so much confusion if they entered the building shooting that no-one would be able to stop them before they reached the Prime Minister's chambers. The element of surprise would almost be enough to guarantee success."

But what about the most horrifying scenario of them all--an unhinged army of the fringe faithful completing their arsenal with nuclear weapons? Alarmingly, the experts are divided. Military journalist Tsuge believes that Aum would have been able to smuggle parts for nuclear warheads from Russia on numerous shipping routes. Prof. Tsuneishi disagrees. "If Aum had wanted to build their own atomic weapons, they would have first had to build their own nuclear power station. That would hardly go unnoticed."

But Brian Jenkins, deputy president of security giant Kroll Associates, sounds a different note of caution. "Even with the most primitive weapons, groups are capable of the most horrifying atrocities," he says. But what stops many terrorists from such indiscriminate violence is the awareness that it would alienate political sympathizers. With religious cults, however, these self-imposed constraints tend to erode, the more fanatical the cult is. Then there are no barriers at all to what they might do."

FOR ALL its inventive dabblings into the possibilities of mass destruction, Aum Shinrikyo, it seems, was light years away from fulfilling the ambitions of its guru. "Aum members lived in a purely imaginary world," says journalist Shoko Egawa. "One that combined primeval fear with a computer-controlled, cartoon version of reality."

But if the Kingdom of Aum was all in the mind, why, then, are so many people--including me--not breathing a sigh of relief? The answer is that Asahara didn't have to blow up Fuji or storm the Diet to hold us in his grip. The Tokyo subway attack and its aftermath have been more than enough. On that sunny spring morning, the sight of commuters spilling out of the subways, streaked in vomit and gulping for breath, sent an unimaginable chill through all of us. It seemed a meaningless act, executed with an invisible deadly weapon that could strike at the most mundane moments of our day. The only advice of one newspaper in case of further attacks was terrifyingly brief: "Flee in the direction in which you see fewer prostrate victims."

The unprecedented incidents that came thick and fast afterwards--gas emissions in Yokohama, the shooting of police chief Takaji Kunimatsu, a letter bomb at Tokyo City Hall--killed no one, but their cumulative effect was profound: they paralyzed Tokyoites almost as effectively as nerve gas itself. One of my co-workers took a Y24,000 taxi ride to Narita rather than risk the trains. "If two people cough at the same time," she said one day in the office, "I start to get edgy." Another friend told me how his eight-year-old son suddenly became withdrawn and took to wearing a surgical mask around the house. On April 15, the day Asahara predicted a catastrophe that "would make the Kobe earthquake seem as minor as a fly landing on one's cheek," I avoided both Shinjuku and the water in my taps.

In the weeks after the attack, daily life took on a surreal quality. Gas masks and canaries sold out, as did translations of a bestselling American guide to "protection, rescue and recovery from destructive cults." Cars were searched, cyclists stopped, litter bins and coin lockers sealed. In department stores and stadiums, security guards would ask: "Is this your bag? Did you pack it yourself?" Gas-masked police were dispatched and a kindergarten evacuated when 30 weather balloons mysteriously fell to earth. Meanwhile, the investigation seemed to get nowhere. Police arrested Aum members on the strangest charges-- "suspicion of riding a stolen bicycle," for instance--while the last-minute neutralization of the Shinjuku cyanide owed more to luck than the long arm of the law.

Now, with Asahara and his fellow suspects behind bars, we have returned to routine but not really to normal. As I write from my Minami-Azabu apartment, only a short distance away from Aum's still-besieged Tokyo headquarters, I've stopped noticing the deafening throb of low-flying police helicopters overhead. I no longer reach for the TV remote as soon as I wake up to check if Tokyo is still standing, nor do I scrutinize my surroundings in crowded places. Could it be that the subsiding fear has been replaced by that most Tokyo of attitudes, fatalism? Perhaps the Aum affair is now part of Tokyo's historical seesaw of creation and destruction, of that collective premonition of disaster that even those of us who weren't born here soon begin to share.

But it would be tragic if Tokyoites end up merely shrugging off this last year of living dangerously. Many crucial questions have yet to be properly answered. Chief among them is: Why wasn't Aum stopped sooner? To point to undeniably noble impulses to respect religious freedom and personal privacy and then say sho ga nai is to miss the point. At the time of the subway attack, there were 110 criminal cases outstanding against Aum upon which the public prosecutors had yet to act--involving such serious matters as extortion, abduction, illegal confinement and wiretapping. In short, Aum had been busy trampling over other people's liberties while its own freedoms had been left intact.

"There is a saying in Korea," says a Tokyo-based Korean businessman: "A bus never stops for you once it has already passed." This, he says in frustration, seems to sum up the police's handling of Aum from the very beginning. "I don't understand why they didn't act earlier."

In support of the authorities, some people say the belated action was inherent in the system--that the police were hampered by the bans on the use of preventive surveillance (an argument used to justify increased undercover police powers under a new law passed on June 13), and the traditional rivalry between prefectural forces. But others believe that the powers-that-be failed to use the perfectly legitimate means they already had; that in their attempts to weigh the two important but sometimes contradictory principles of personal freedom and public safety, they simply got the balance wrong. Fatally wrong.

In any case, respect for religious freedom can hardly explain the nine-month time-lag between the Matsumoto and Tokyo sarin attacks, during which time the police cruelly encouraged the fallacy that a company employee called Yoshiyuki Kono was Matsumoto's phantom poisoner. The police stuck to their story long after some sections of the media had begun pointing at Aum, and it is only in the last few weeks that Kono's name has been cleared of an atrocity that has left his wife in a vegetative coma.

After the Tokyo attack, why did the tens of thousands of police and armed forces personnel seem so powerless to halt the flow of terrorist acts? As one journalist notes, "What we witnessed was a 19th-century police force tackling a 21st-century crime." For me, the abiding illustration of this is the image of police officers raiding Aum facilities clutching canaries, while Aum was equipped with its own sophisticated Russian-made nerve gas detector. (The notion of using yellow birds in law enforcement seemed so perplexing to one friend that she missed the point entirely: watching the TV pictures, she assumed the police had just rescued the canaries from Aum.)

So why was Aum allowed to go so far? Some say the authorities are unlikely ever to provide an answer. Instead, they attempt to drown the question in the steady, stage-managed drip-drip-drip of confessions now being leaked from police central and filtered through a grateful media corps.

Then there are the nation's glorious leaders. The public's steady erosion of faith in authority that reached mudslide proportions during the Kobe earthquake, seems now only to be outstripped by the authorities' lack of faith in themselves. In late March, Prime Minister Tomiichi Murayama was heard to moan tactlessly how unfair it was that both the Hanshin earthquake and the Aum affair happened during his term of office. Then he apologized. Then came April's Yokohama gassings. "Well, at least it wasn't sarin," he said, "so that's good." He apologized again. The next day, he congratulated the police for making so many legally dubious arrests, praising them for "sailing close to the wind." Although he later "clarified" the statement, Murayama's public approval rating has since hit record lows.

It is surprising and revealing, however, that the people who are under arrest as the real villains in this affair--the members of Aum themselves--are not targets of particularly widespread public vitriol. In fact, it is sometimes quite the opposite. "I can empathize with them to a point," one 22-year-old male student of international relations told me. "If I ever got really depressed, I can imagine becoming involved with a cult." Another friend told me that she understands the dissatisfactions of Aum's doctors, physicists and PR chiefs. "These people sat next to me at school, watched the same TV programs, went through all the same pressures."

There are inklings in these attitudes of how a small minority of the educated elite became drawn into a deluded and potentially devastating plan to overthrow their own society. Aum's own Armageddon was not to be. But when the Aum rollercoaster slows, and the question "What next?" is no longer relevant, the only one that should replace it is "What now?" Could it all happen again? Professor Kei'ichi Tsuneishi believes the answer to that one lies within. "We like to think that Aum was a special case, an aberration. But our society created this cult. Unless we look to ourselves, we could create it again."