It was inconceivable. If the data was correct, Tankado and hispartner were the same person. Susan's thoughts weresuddenly disconnected. She wished the blaring horn would stop. Why doesn't Strathmore turn that d.a.m.n thing off?

Hale twisted on the floor, straining to see Susan. "Whatdoes it say? Tell me!"

Susan blocked out Hale and the chaos around her. EnseiTankado is North Dakota... .

She reshuffled the pieces trying to make them fit. If Tankadowas North Dakota, then he was sending E-mail to himself . .. which meant North Dakota didn't exist.

Tankado'spartner was a hoax.

North Dakota is a ghost, she said to herself. Smokeand mirrors.

The ploy was a brilliant one. Apparently Strathmore had beenwatching only one side of a tennis match. Since the ball keptcoming back, he a.s.sumed there was someone on the other side of thenet. But Tankado had been playing against a wall. He had beenproclaiming the virtues of Digital Fortress in E-mail he'dsent to himself. He had written letters, sent them to an anonymousremailer, and a few hours later, the remailer had sent them rightback to him.

Now, Susan realized, it was all so obvious. Tankado had wanted the commander to snoop him ... he'd wantedhim to read the E-mail. Ensei Tankado had created an imaginaryinsurance policy without ever having to trust another soul with hispa.s.s-key. Of course, to make the whole farce seem authentic,Tankado had used a secret account ... just secret enough to allayany suspicions that the whole thing was a setup.

Tankado was hisown partner. North Dakota did not exist. Ensei Tankado was aone- man show.

A one-man show.

A terrifying thought gripped Susan. Tankado could have usedhis fake correspondence to convince Strathmore of just aboutanything.

She remembered her first reaction when Strathmore told her aboutthe unbreakable algorithm. She'd sworn it was impossible. Theunsettling potential of the situation settled hard in Susan'sstomach. What proof did they actually have that Tankado had really created Digital Fortress? Only a lot of hype in hisE-mail. And of course ...

TRANSLTR. The computer had been lockedin an endless loop for almost twenty hours. Susan knew, however,that there were other programs that could keep TRANSLTR busy thatlong, programs far easier to create than an unbreakablealgorithm.

Viruses.

The chill swept across her body.

But how could a virus get into TRANSLTR?

Like a voice from the grave, Phil Chartrukian gave the answer.Strathmore bypa.s.sed Gauntlet!

In a sickening revelation, Susan grasped the truth. Strathmorehad downloaded Tankado's Digital Fortress file and tried tosend it into TRANSLTR to break it. But Gauntlet had rejected thefile because it contained dangerous mutation strings.

NormallyStrathmore would have been concerned, but he had seenTankado's E-mail- Mutation strings are the trick!Convinced Digital Fortress was safe to load, Strathmore bypa.s.sedGauntlet's filters and sent the file into TRANSLTR.

Susan could barely speak. "There is no DigitalFortress," she choked as the sirens blared on. Slowly, weakly,she leaned against her terminal. Tankado had gone fishing for fools... and the NSA had taken the bait.

Then, from upstairs, came a long cry of anguish. It wa.s.strathmore.

CHAPTER 86 Trevor Strathmore was hunched at his desk when Susan arrivedbreathless at his door.

His head was down, his sweaty headglistening in the light of his monitor. The horns on the sublevelsblared.

Susan raced over to his desk. "Commander?"

Strathmore didn't move.

"Commander! We've got to shut down TRANSLTR!We've got a-"

"He got us," Strathmore said without looking up."Tankado fooled us all ..."

She could tell by the tone of his voice he understood. All ofTankado's hype about the unbreakable algorithm ...auctioning off the pa.s.s-key-it was all an act, a charade.Tankado had tricked the NSA into snooping his mail, tricked theminto believing he had a partner, and tricked them into downloadinga very dangerous file.

"The mutation strings-" Strathmore faltered.

"I know."

The commander looked up slowly. "The file I downloaded offthe Internet ... it was a ..."

Susan tried to stay calm. All the pieces in the game hadshifted. There had never been any unbreakable algorithm-neverany Digital Fortress. The file Tankado had posted on the Internetwas an encrypted virus, probably sealed with some generic,ma.s.s- market encryption algorithm, strong enough to keep everyoneout of harm's way- everyone except the NSA. TRANSLTR hadcracked the protective seal and released the virus.

"The mutation strings," the commander croaked."Tankado said they were just part of the algorithm."Strathmore collapsed back onto his desk.

Susan understood the commander's pain. He had beencompletely taken in. Tankado had never intended to let any computercompany buy his algorithm. There was no algorithm. The wholething was a charade. Digital Fortress was a ghost, a farce, a pieceof bait created to tempt the NSA. Every move Strathmore had made,Tankado had been behind the scenes, pulling the strings.

"I bypa.s.sed Gauntlet." The commander groaned.

"You didn't know."

Strathmore pounded his fist on his desk. "I shouldhave known! His screen name, for Christ's sake! NDAKOTA! Lookat it!"

"What do you mean?" "He's laughing at us! It's a G.o.dd.a.m.nanagram!"

Susan puzzled a moment. NDAKOTA is an anagram? Shepictured the letters and began reshuffling them in her mind. Ndakota ... Kado-tan ... Oktadan ... Tandoka .

. . Herknees went weak. Strathmore was right. It was as plain as day. Howcould they have missed it? North Dakota wasn't a reference tothe U.S. state at all-it was Tankado rubbing salt in thewound! He'd even sent the NSA a warning, a blatant clue thathe himself was NDAKOTA. The letters spelled TANKADO. But the bestcode- breakers in the world had missed it, just as he hadplanned.

"Tankado was mocking us," Strathmore said.

"You've got to abort TRANSLTR," Susandeclared.

Strathmore stared blankly at the wall.

"Commander. Shut it down! G.o.d only knows what's goingon in there!"

"I tried," Strathmore whispered, sounding as faint a.s.she'd ever heard him.

"What do you mean you tried?"

Strathmore rotated his screen toward her. His monitor had dimmedto a strange shade of maroon. At the bottom, the dialogue boxshowed numerous attempts to shut down TRANSLTR. They were allfollowed by the same response: SORRY. UNABLE TO ABORT.

SORRY. UNABLE TO ABORT.

SORRY. UNABLE TO ABORT.

Susan felt a chill. Unable to abort? But why? She fearedshe already knew the answer.

So this is Tankado's revenge?Destroying TRANSLTR! For years Ensei Tankado had wanted theworld to know about TRANSLTR, but no one had believed him. Sohe'd decided to destroy the great beast himself. He'dfought to the death for what he believed-the individual'sright to privacy.

Downstairs the sirens blared.

"We've got to kill all power," Susan demanded."Now!"

Susan knew that if they hurried, they could save the greatparallel processing machine.

Every computer in the world-fromRadio Shack PCs to NASA's satellite control systems-had abuilt-in fail-safe for situations like this. It wasn't aglamorous fix, but it always worked. It was known as "pullingthe plug."

By shutting off the remaining power in Crypto, they could forceTRANSLTR to shut down. They could remove the virus later. It wouldbe a simple matter of reformatting TRANSLTR's hard drives.Reformatting would completely erase the computer'smemory-data, programming, virus, everything. In mostcases, reformatting resulted in the loss of thousands of files,sometimes years of work. But TRANSLTR was different-it couldbe reformatted with virtually no loss at all.

Parallel processingmachines were designed to think, not to remember. Nothing wasactually stored inside TRANSLTR. Once it broke a code, it sent theresults to the NSA's main databank in order to- Susan froze. In a stark instant of realization, she brought herhand to her mouth and m.u.f.fled a scream. "The maindatabank!"

Strathmore stared into the darkness, his voice disembodied.He'd apparently already made this realization. "Yes,Susan. The main databank... ."

Susan nodded blankly. Tankado used TRANSLTR to put a virus inour main databank.

Strathmore motioned sickly to his monitor. Susan returned hergaze to the screen in front of her and looked beneath the dialoguebox. Across the bottom of the screen were the words: TELL THE WORLD ABOUT TRANSLTR ONLY THE TRUTH WILL SAVE YOU NOW ...

Susan felt cold. The nation's most cla.s.sified informationwas stored at the NSA: military communication protocols, SIGINTconfirmation codes, ident.i.ties of foreign spies, blueprints foradvanced weaponry, digitized doc.u.ments, trade agreements- thelist was unending.

"Tankado wouldn't dare!" she declared."Corrupting a country's cla.s.sified records?"

Susancouldn't believe even Ensei Tankado would dare attack the NSAdatabank. She stared at his message.

ONLY THE TRUTH WILL SAVE YOU NOW "The truth?" she asked. "The truth aboutwhat?"

Strathmore was breathing heavily. "TRANSLTR," hecroaked. "The truth about TRANSLTR."

Susan nodded. It made perfect sense. Tankado was forcing the NSAto tell the world about TRANSLTR. It was blackmail after all. Hewas giving the NSA a choice- either tell the world aboutTRANSLTR or lose your databank. She stared in awe at the textbefore her. At the bottom of the screen, a single line was blinkedmenacingly.

ENTER Pa.s.s-KEY Staring at the pulsating words, Susan understood-the virus,the pa.s.s-key, Tankado's ring, the ingenious blackmail plot.The pa.s.s-key had nothing to do with unlocking an algorithm; it wasan antidote. The pa.s.s-key stopped the virus. Susan had reada lot about viruses like this-deadly programs that included abuilt-in cure, a secret key that could be used to deactivate them.Tankado never planned to destroy the NSA databank-he justwanted us go public with TRANSLTR! Then he would give us thepa.s.s-key, so we could stop the virus!

It was now clear to Susan that Tankado's plan had goneterribly wrong. He had not planned on dying. He'd planned onsitting in a Spanish bar and listening to the CNN press conferenceabout America's top-secret code-breaking computer. Thenhe'd planned on calling Strathmore, reading the pa.s.s-key offthe ring, and saving the databank in the nick of time. After a goodlaugh, he'd disappear into oblivion, an EFF hero.

Susan pounded her fist on the desk. "We need that ring!It's the only pa.s.s-key!" She nowunderstood-there was no North Dakota, no secondpa.s.s-key. Even if the NSA went public with TRANSLTR, Tankado was nolonger around to save the day.

Strathmore was silent.

The situation was more serious than Susan had ever imagined. Themost shocking thing of all was that Tankado had allowed it to gothis far. He had obviously known what would happen if the NSAdidn't get the ring-and yet, in his final seconds oflife, he'd given the ring away. He had deliberately tried tokeep it from them. Then again, Susan realized, what could she expect Tankado to do-save the ring for them, when hethought the NSA had killed him?

Still, Susan couldn't believe that Tankado would haveallowed this to happen. He was a pacifist. He didn't want towreak destruction; all he wanted was to set the record straight.This was about TRANSLTR. This was about everyone's right tokeep a secret.

This was about letting the world know that the NSAwas listening. Deleting the NSA's databank was an act of.a.ggression Susan could not imagine Ensei Tankado committing.

The sirens pulled her back to reality. Susan eyed thedebilitated commander and knew what he was thinking. Not only werehis plans for a back door in Digital Fortress shot, but hiscarelessness had put the NSA on the brink of what could turn out tobe the worst security disaster in U.S. history.

"Commander, this is not your fault!" sheinsisted over the blare of the horns. "If Tankado hadn'tdied, we'd have bargaining power-we'd haveoptions!"

But Commander Strathmore heard nothing. His life was over.He'd spent thirty years serving his country. This was supposedto be his moment of glory, his piece de resistance-aback door in the world encryption standard. But instead, he hadsent a virus into the main databank of the National SecurityAgency. There was no way to stop it-not without killing powerand erasing every last one of the billions of bytes ofirretrievable data. Only the ring could save them, and if Davidhadn't found the ring by now ...

"I need to shut down TRANSLTR!" Susan took control."I'm going down to the sublevels to throw the circuitbreaker." Strathmore turned slowly to face her. He was a broken man."I'll do it," he croaked.

He stood up, stumbling ashe tried to slide out from behind his desk.

Susan sat him back down. "No," she barked. "I'm going." Her tone left no room fordebate.

Strathmore put his face in his hands. "Okay. Bottom floor.Beside the freon pumps."

Susan spun and headed for the door. Halfway there, she turnedand looked back.

"Commander," she yelled. "This isnot over. We're not beaten yet. If David finds the ringin time, we can save the databank!"

Strathmore said nothing.

"Call the databank!" Susan ordered. "Warn themabout the virus! You're the deputy director of the NSA.You're a survivor!"

In slow motion, Strathmore looked up. Like a man making thedecision of a lifetime, he gave her a tragic nod.

Determined, Susan tore into the darkness.

CHAPTER 87

The Vespa lurched into the slow lane of the Carretera de Huelva.It was almost dawn, but there was plenty of traffic-youngSevillians returning from their all-night beach verbenas. A van ofteenagers laid on its horn and flew by. Becker's motorcyclefelt like a toy out there on the freeway.

A quarter of a mile back, a demolished taxi swerved out onto thefreeway in a shower of sparks. As it accelerated, it sideswiped aPeugeot 504 and sent it careening onto the gra.s.sy median.

Becker pa.s.sed a freeway marker: SEVILLA CENTRO-2 KM. If hecould just reach the cover of downtown, he knew he might have achance. His speedometer read 60 kilometers per hour. Two minutesto the exit. He knew he didn't have that long.

Somewherebehind him, the taxi was gaining. Becker gazed out at the nearinglights of downtown Seville and prayed he would reach themalive.

He was only halfway to the exit when the sound of sc.r.a.ping metalloomed up behind him. He hunched on his bike, wrenching thethrottle as far as it would go. There was a m.u.f.fled gunshot, and abullet sailed by. Becker cut left, weaving back and forth acrossthe lanes in hopes of buying more time. It was no use. The exitramp was still three hundred yards when the taxi roared to within afew car lengths behind him.

Becker knew that in a matter of secondshe would be either shot or run down. He scanned ahead for anypossible escape, but the highway was bounded on both sides by steepgravel slopes. Another shot rang out. Becker made his decision.