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Aired October 20, 2001 - 20:00 ET
THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.
THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.
ANNOUNCER: September 11, two planes smash into the World Trade Center towers. A third plane strikes the Pentagon. A fourth crashes in Pennsylvania.
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GEORGE W. BUSH, PRESIDENT OF THE UNITED STATES: Thousands of lives were suddenly ended by evil.
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ANNOUNCER: Who's behind the attacks? Thousands of federal investigators launch into action.
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ROBERT MUELLER, FBI DIRECTOR: We will leave no stone unturned.
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ANNOUNCER: Within days, agents identify the 19 alleged hijackers, but how did they do it? Who planned it? Who financed it?
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BUSH: We know we got a suspect.
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WILLOW BAY, CNN ANCHOR: Welcome to CNN PRESENTS. I'm Willow Bay. It is unlike anything the world has ever seen -- a global campaign to route out, round up and cut off terrorists wherever they hide. The task is daunting. It relies on police forces, intelligent services and banking systems around the world.
As the search for clues continues and now expands to include the threat of anthrax, we'll spend the next hour taking a look at an investigation that began on September 11. A complex trail littered with hot leads, dead ends, lucky breaks and missed opportunities. We'll tell you what investigators know at this point and what they don't. We begin with a chilling glimpse into the mindset of the suspected hijackers from CNN's Kelli Arena. (BEGIN VIDEOTAPE)
KELLI ARENA, CNN JUSTICE CORRESPONDENT (voice-over): We have their last images and the lasting images they left us. But how could the 19 suspected hijackers and whoever may have helped them hide in plain sight in the weeks and months before September 11, fooling everyone to such deadly effect.
DIANE SURMA, HOTEL OWNER: Very nice, very quiet, no problem. I didn't have to be suspicious because they were nice people.
ARENA: Clues to the hijackers' success may come from these pages, their Al Qaeda manuals, blueprints for terror, used to train members in the art and science of undercover operations. Everything from working in cells to blending in to their community is covered in these pages. The manuals were introduced into evidence earlier this year at the trail of Al Qaeda members in New York City charged in connection with the 1998 bombings of U.S. embassies in Kenya and Tanzania.
UNIDENTIFIED MALE: All documents of the undercover brother, such as identity cards and passport, should be falsified.
ARENA: Even before the men arrived in the United States, investigators believed some of them got their visas based on false identities.
PAUL VIRTUE, FORMER INS GENERAL COUNSEL: There is a problem with people adopting the identities of others. Sometimes they use photo substitutes on their passports or they've acquired a passport of somebody they look like.
ARENA: In 30 million visas issued every year, no one seemed to notice as the men arrived in the United States. But not all the suspected terrorists play by the book. Some like Ziad Jarrah used their real names. Investigators say Jarrah had no fear of being caught because there was simply no reason to look for him.
BEN VENZKE, TERRORISM EXPERT: They would want people that could get into the country, preferably legally, preferably people that we weren't aware of, they don't have a history.
UNIDENTIFIED MALE: After receiving information about the target, the operational plan is created. The Commander makes the tactical plan.
ARENA: It is not clear when the targets were chosen or even who the Commander was. In past Al Qaeda operations, such as the embassy bombings, the Commander left before the actual attack took place. And like the previous attacks, investigators say, this one seems to have been on the drawing board for years.
One example, this man, Lotfi Raissi, entered the U.S. to begin flight training in 1996. He became a flight instructor. He's now being held in Britain. U.S. and British officials say Raissi made several trips between the U.S. and the U.K. He even flew with suspected hijacker pilot Hani Hanjour from Las Vegas to Phoenix on June 23 to oversee the flight simulator training of Hanjour and three other alleged hijack pilots.
UNIDENTIFIED MALE: A special operation must have stages. These stages are integrated and inseparable. One, research stage; two, planning stage; three, execution stage.
ARENA: The suspected hijackers apparently carried out their research and their planning at the same time. One came to Bowie, Maryland, just some 30 miles from Washington D.C. to rent a plane. Hani Hanjour was not deemed proficient enough to fly on his own, but one flight instructor says he enough training to ultimately perform the task of flying American Flight 77 into the Pentagon.
MARCEL BERNARD, FLIGHT INSTRUCTOR: We believe that even though he didn't necessarily have experience in jets that once the airplane was airborne that he could have easily pointed it in any direction he wanted to and crash it into a building or whatever. It would be a real feasibility, a real possibility.
UNIDENTIFIED MALE: Avoid seclusion and isolation from the population. Use a non-Muslim appearance.
ARENA: The suspects cut their hair, trimmed or shaved their beards. They used ATMs, ate at restaurants, went shopping and traveled around the country, staying in apartments and hotels from south Florida to southern California, Maryland to Arizona.
JIM COLLINS, LAUREL, MARYLAND POLICE DEPARTMENT SPOKESMAN: These people blend in so well you could have been with them shopping, you could have passed them on the street and you'd never know it.
UNIDENTIFIED MALE: Do not raise suspicions of the security people or even the normal people. Each group does not know anything about the other group.
ARENA: Blending in is just part of the challenge. The manuals urged the men using false documents to carry only one at a time and memorize their cover stories. And information is to be compartmentalized to work in cells just in case one person should be picked up by police.
MAGNUS RANSTORP, CNN TERRORISM ANALYST: Here we are dealing with at least 19 individuals and should one of them have been arrested for engaging in any criminal activity, that could have blown the cover for at least part of the operations and would have given law enforcement officials the clue to what was about to transpire.
UNIDENTIFIED MALE: The operation should be appropriate to the participants' physical and mental abilities.
ARENA: Some of the men made an effort to stay in shape, working out in gyms in Florida and Georgia not only to stay fit but to learn defensive skills, investigators believed, were later used to keep passengers at bay.
Bert Rodriguez says he trained one of the alleged hijackers at gym in Florida.
BERT RODRIGUEZ, PERSONAL TRAINER: I'm sure that that's why he took the training. They knew that they were going to be able to -- to confront any attack much better.
UNIDENTIFIED MALE: Communication is the mainstay of the movement. However, it can be to our advantage if we use it well and it can be a knife dug into our back if we do not consider and take necessary security measures.
ARENA: Places such as public libraries, like this one, in Delray Beach, Florida, were part of their secure communications. Using computers, investigators say, the hijackers sent messages, even booked airline tickets.
UNIDENTIFIED MALE: Secrecy should be used even with the closet people, for deceiving the enemies is not easy.
ARENA: As the 19 suspects went through their final hours, investigators say, it's still not clear whether all of them knew their full mission, not only to hijack the planes but crash them into buildings in New York and Washington.
RANSTORP: I do not believe that all of the hijackers knew that they would meet their destiny in that fashion.
ARENA: But for those who did know, there was one final order from the manual -- a quote from the Koran.
UNIDENTIFIED MALE: "Against them make ready your strength to the utmost of your power, including steeds of war, to strike terror into the hearts of the enemies of Allah and your enemies."
BAY: Investigators say they found detailed terrorist instructions among the articles left behind by the September 11 hijackers, including those of suspected ringleader, Mohammed Atta. Who was Atta? That story when we return.
BAY: He was an inconspicuous man with a consuming hatred for America; a hatred that investigators say was unleashed in the worst terrorist attacks in U.S. history. But Mohammed Atta is suspected of being more than just a conspirator. He is suspected of being a linchpin, a ringleader of the September 11 hijackers. Who was Mohammed Atta? Here's CNN's Sheila MacVicar.
SHEILA MACVICAR, CNN CORRESPONDENT (voice-over): What we know now about Mohammed Atta cannot begin to explain what took him from middle-class in secular Cairo where he is remembered as a shy boy who adored his mother through university in Hamburg where colleagues describe him as courteous, even kind. What turned him from this man into a suspected suicide terrorist believed responsible for mass murder? There are questions we cannot answer, but there is a portrait here that offers some clues.
Whatever the reason for the change in Mohammed Atta, it began here in Hamburg in 1996. He studied urban planning. At age 27, he began thinking about his own death. He wrote a will and for 15 months, he disappeared. American investigators now suspect he had been recruited and sent to Afghanistan. When he reappeared, he had changed.
PROFESSOR DITTMAR MACHULE, PROFESSOR OF URBAN PLANNING (through translator): He was very religious. He used to pray regularly. He was strict about fasting.
MACVICAR: And it is now clear that while he wrote his thesis in 1999, he began to plan. In an apartment at 54 Marian Street, the first of the key figures came together -- Mohammed Atta, Marwan Al- Shehhi, Ziad Jarrah. There were three others, now fugitives, suspected of providing logistics and perhaps the connections to Al Qaeda.
KLAUS NEIDHARDT, GERMAN FEDERAL CRIMINAL POLICE: They were a group. They had close relationships with one -- with each other. We don't know everything about preparations, about the planning and how it works -- what worked out.
MACVICAR: Late that year, Mohammed Atta and some of the other suspected hijackers reported their passports stolen, a ploy German investigators suspect to get rid of indications of travel to Afghanistan. Travels that could set off alarm bells.
By the end of 1999, the evidence strongly suggests that Mohammed Atta knew what he was going to do and how he was going to die.
On May 18, 2000, at the U.S. embassy in Berlin, Mohammed Atta got a multiple entry visa for the United States. On June 2, he drove to Prague. He stayed just 24 hours.
(on-camera): Intelligence sources tell CNN that Mohammed Atta met their Prague Airport with Samir Alomari then station chief for Iraqi intelligence in the Czech Republic. The meeting took place in public and sources say it was observed by Czech intelligence agents who were watching Mr. Alomari. Nothing else is publicly known about that meeting.
We do know that on June 3, 2000, Mohammed Atta flew to New York. From Newark Airport, he would have been able to see the twin towers. He began his life of hiding in plain sight. An inconspicuous man leading an inconspicuous life, leading a law, devoted to a purpose. The suspected leader was in place.
In early July, Mohammed Atta showed up in Florida at Huffman Aviation. He wrote a check for $25,000. His instructors found him arrogant.
RUDI DEKKERS, HUFFMAN AVIATION: My chief pilot stated to Atta, "If you do not change, if you not listen to the instructions -- the instructions I'm giving, there's one way. That's the exit."
MACVICAR: By the end of that summer, the six hijackers the FBI suspects piloted the planes were all in flying schools across the United States. On December 21, 2000, Mohammed Atta graduated. He got his pilot's license. It was time to move to the next phase and Mohammed Atta began to travel.
Twelve days later, he flew to Madrid, the first of two visits to Spain. Juan Catino (ph) is the chief of Spain's National Police Force. Of that first trip, he says, his investigators cannot find Atta's trail.
JUAN CATINO, CHIEF, SPAIN'S NATIONAL POLICE FORCE (through translator): Atta was in Madrid on the fourth of January, but we don't know when he left. With forged identification, he may have traveled to another European country and made contact elsewhere.
MACVICAR: Within a week, Mohammed Atta was back in the United States. In February, he was in Bell Glades, Florida inspecting crop dusters. At this bank, he tried to get a loan to buy one.
In March, say German investigators, Mohammed Atta went back to Europe. He was spotted in Hamburg and CNN has learned again in Prague, again meeting with the same Iraqi intelligence agent.
All through this spring, in groups of two's or three's, the remaining suspected hijackers began arriving in the United States. On June 29, 2001, the last two flew from Zurich to New York. That same day, another piece of the plot in place, Mohammed Atta flew to Las Vegas. He stayed here at the Econo Lodge. Investigators believe other suspected pilot hijackers, part of that first group to arrive in the U.S., might have been in Las Vegas at the same time.
On July 8, Mohammed Atta began another puzzling trip to Europe. First, he flew from Miami to Zurich. Swiss prosecutors say he spent two-and-a-half hours in the airport. He used an ATM card four times and withdrew 1,700 Swiss francs. In Duty Free, he bought two Swiss Army knives and some Swiss chocolate and then he flew back to Spain to Madrid.
COTINO (through translator): No terrorist moves by chance. In our experience, terrorists use postmen to deliver messages personally. I believe Atta came to deliver a message.
MACVICAR: Mohammed Atta rented a car in Madrid and then he disappeared for nearly a week. Spanish investigators think he drove here to Barcelona. That under a false name, it is possible he took another plane to another country in Europe or another destination in Spain. When he resurfaced on July 14, it was in the eastern Spanish town of Tarragona at this prison. Mohammed Atta came to see a prisoner; an Algerian jailed after a knife fight, a man with a history of forging documents. It is not yet clear how they knew each other.
Two days later, he was in the nearby beach resort of Salvo (ph).
(on-camera): The Spanish police know Mohammed Atta was here and they say they think he came here for a reason. They believe there was an important meeting held in this town probably on July 16. They just aren't sure yet who attended or why.
(voice-over): Just minutes after Mohammed Atta checked into this hotel, Spanish sources say, two other men arrived. Spanish police are now examining whether it met with another group of suspected terrorists arrested from September 11. They are accused of plotting to blow up the American embassy in Paris.
COTINO (through translator): There are suspicions that a third party could have brought them together.
MACVICAR: On August 12, Mohammed Atta returned to Las Vegas. Based on flight records, investigators believe he met with other suspected hijackers. Now, they want to know was this meeting a month before the attack, a final planning session? On August 28, he bought his ticket for American Airlines Flight 11. He used his Frequent Flyer card.
On Friday, September 7, he was at Shuckums Bar in Hollywood, Florida with Marwan Al-Shehhi who had come from Hamburg with him. At least one of them was drinking vodka. Both were boasting about being American airline pilots.
On September 10 at 5:43 p.m., Mohammed Atta and another suspected hijacker checked into the Comfort Inn in Portland, Maine.
CHARLES PROTT, SPECIAL AGENT IN CHARGE: The next time that we had them; we picked them up on surveillance camera at the Fast Green ATM. This photograph here is of Abdul Alomari. You can see Mohammed in the background there.
MACVICAR: In public, it was the most mundane of evenings -- pizza for dinner, filling up the car, a quick trip to Wal-Mart.
PROTT: This is at 9:22 p.m. The Wal-Mart is located at 451 Paine Road in Scarborough.
MACVICAR: And then a retreat to their hotel room. If they followed the assassin's manual found after their death, they spent the night renewing their oath to die.
These are the last pictures we have of Mohammed Atta. It is early in the morning of September 11 at the airport in Portland, Maine. Clean-shaven, his hair cropped short, Mohammed Atta has just cleared airport security. We know what happened next.
BAY: As we told you, the terrorist attacks of September 11 required extraordinary dedication and extensive planning. They also required deep of reserve of cash. Coming up, targeting those who underwrite murder.
(COMMERCIAL BREAK) BAY: Money, it is the lifeblood of terrorism. And the global financial networks of terror are as complex as they are gladded with cash. The numbers are staggering. The source, elusive. CNN's Allan Dodds Frank is following terror's money trail in a battle where currency can be as lethal as a bullet.
ALAN DODDS FRANK, CNN FINANCIAL NEWS CORRESPONDENT (voice-over): Even more than religious fervor, it takes money to build and sustain terrorist networks -- lots of money for food, wages, and shelter no matter how modest, for training, weapons and communications, for transportation and support for terrorists, says the U.S. government in more than 60 countries. So where did the money come from?
Initially, from Osama bin Laden's own pocket. Along with his more than 50 brothers and sisters, he inherited a portion of his father's multibillion-dollar empire, the Saudi bin Laden Group. His share about $60 million.
In the early 1980s, bin Laden worked with operatives from U.S. intelligence, the Pakistani military and Arab states. They ran a wide-ranging covert network that recruited and financed Muslim fighters to battle the Soviet army. Using the covert techniques he learned, he built his organization, Al Qaeda, with fellow Muslim war veterans.
WILLIAM WECHSLER, FORMER NATIONAL SECURITY COUNCIL: It was this network that followed Osama bin Laden that he kept with him when he left Afghanistan the first time. He went back to Saudi Arabia, then to Sudan and then to Afghanistan. And all that -- during that period, it built. It got more complicated and it got moved to terrorist ends.
FRANK: But he lost millions when the Bank of Credit and Commerce International, the heart of the old Covert Financial Network collapsed in a global money laundering scandal in 1991.
(on-camera): So that year, when he moved to Sudan, bin Laden set up the Alshamal Islamic Bank, which investigators believe, he used to send money to Al Qaeda cells around the world.
(voice-over): His organization kept a low profile, matching the images of the September 11 suspected hijackers who stayed in cheap motels and apartments and shopped at Wal-Mart. Still, staging the attacks was not cheap.
JIMMY GURULE, UNDER SECRETARY OF ENFORCEMENT, U.S. TREASURY DEPARTMENT: We're talking at -- at a minimum, is in the millions -- in the millions of dollars to underwrite just the expenses related to this operation.
FRANK: In the Clinton administration, William Wechsler led the hunt for bin Laden's money.
WECHSLER: The money that is used for terrorism is still being raised. It's still being solicited from people throughout the Muslim world. It's still being raised under the guides of charitable organizations. It's still coming from business center guises, some legitimate, some illegitimate.
FRANK: Contributors to charities claiming to aid Muslim refugees, in fact, maybe donating to bin Laden fronts. Drug addicts, too, may contribute unwittingly since investigators say one of his biggest sources of money is the drug trade.
In recent years, the poppy fields of Afghanistan have produced as much as three-quarters of the world's opium, the base ingredient of heroine. Heroine taxed by the Taliban and moved in caravans protected by Al Qaeda gunmen.
TONY BLAIR, BRITISH PRIME MINISTER: The Al Qaeda network and the Taliban regime have funded, in large part, on the drugs trade. Ninety percent of all heroine sold on British streets originates from Afghanistan.
FRANK: Then there's protection money. U.S. government sources believe rich, Arab businessmen have succumbed to extortion by Al Qaeda.
SEN. JOHN KERRY (D), MASSACHUSETTS: The number of wealthy people have effectively paid protection to Osama bin Laden, not unlike protection money to organized crime that have been paid in New York or other cities over the course of our history.
FRANK: Countries, the U.S. says, sponsor terrorism -- among them, Iraq, Iran, Libya and Syria also have lent bin Laden a hand.
KERRY: What we do know is there are contributions in kind, i.e. food, shelter, sort of support by just having a base of operations in a particular country.
FRANK: Raising money is only the beginning. Money laundering experts say bin Laden's associates exploit every avenue, including the practically paperless underground cash transfer system known as the wallet.
They used Islamic banks in the in Middle Eastern money centers, such as Dubai, to make the transition between east and west. And the favorite places to put money? Multi-national banks.
DAN KARSON, KROLL ASSOCIATES: If you're dealing with sums of money that are small, you are flying well under the radar screen. You are escaping scrutiny.
FRANK: Barclays, Bank of America, Citicorp, Credit Suisse, Credit Lyonnais, Commerce Bank and Deutsche Bank are among the money center banks that have frozen accounts. As for the bin Laden family business, it maintains close public ties with the Saudi royal family. But the privately held Saudi bin Laden group shrouds its finance in secrecy.
The family says it has had no dealings with the world's most wanted terrorist since his Saudi citizenship was revoked in 1994. But as government officials note, family ties are family ties. So doubts linger.
BAY: From cutting off terrorism's cash flow, to catching a lucky break; coming up: How the arrest of one man may have prevented a second wave of attacks.
BAY: In an investigation of this size and complexity, one single arrest may lead authorities to a dead end or to bonanza. Such is case of Djamel Beghal, whose arrest in Dubai led investigators to terrorist suspects around the Europe and may have prevented a second wave of attacks following September 11.
CNN Diana Muriel examines a domino effect in the fight against terrorism.
DIANA MURIEL, CNN CORRESPONDENT (voice-over): The arrest of this man, French Algerian Djamel Beghal, was a major breakthrough for French prosecutors tracking the operations of terrorists in Europe. He'd been caught by airport authorities in the United Arab emirates, trying to fly to Europe on a fake French passport.
Intelligence sources close to investigators in the UAE, say that under days of interrogation, Beghal told of planned attacks in France, including the U.S. embassy in Paris, as well as details of terrorist cells operating in Rotterdam in the Netherlands and another in Paris.
Intelligence sources say Beghal interrogation was tough. They didn't rule out the use of torture. At the request of the French authorities, Beghal was extradited to France last month for further questioning by French anti-terror magistrates.
ALAIN MARSAUD, FOUNDER, FRENCH ANTI-TERROR PROSECUTOR (through translator): Beghal was accused of being associated with a terrorist organization. Now we have to prove that he had started to put his terrorist plans into action. This will take a long time. He confessed in Dubai, but he's retracted his testimony here in France.
MURIEL: Retraction or not, the leads were a bonanza for European police. By early August, Dutch police had a full person cell under surveillance in Rotterdam. Then, intelligence sources say, police learned of a connection between the cell in Rotterdam and another based here in Brussels, a cell allegedly headed by a Tunisian ex- soccer player, Nizar Trabelsi.
Police say Trabelsi and Beghal go back a long way. Both men had lived in London in the late 90s, where Abu Katada (ph) preached his sermons. A fundamentalist Muslim cleric, Katada (ph) lived in this house in West London. Here, investigative sources say, he nurtured two of his followers, Beghal and Trabelsi. Through Katada (ph), intelligence sources say, both Beghal and Trabelsi went to Afghanistan to two terrorist training camps. It was on Beghal's return trip, sources say, he was arrested in Dubai. Trabelsi meanwhile moved to Brussels, staying out of sight. There, French investigators say he put into practice recruiting and surveillance skills he'd learned in Afghanistan.
Anne Marie Lisant, Belgium parliamentarian, who has been following police investigations into European terror cells, says Belgium was a perfect base from which to plan attacks.
ANNE MARIE LISANT, BELGIUM PARLIAMENTARY: We are not target, but we are such a quiet country, that we could be a good preparation country.
MURIEL: Intelligence sources believe Trabelsi was using the Rotterdam cell as a logistics base for the planned attack on the U.S. embassy in Paris and possibly another attack on NATO headquarters in Brussels. Two days after the attack on the Pentagon and the World Trade Center, as part of the coordinated operation, police in Rotterdam and Brussels moved in. Four arrests were made in Rotterdam.
Trabelsi and a Belgian Moroccan were arrested in Brussels at separate addresses. Belgian police also raided this Egyptian snack bar in the heart of Brussels. Here, they found 220 pounds of sulfur and 13 gallons of acetone, the basic ingredients for a bomb big enough, experts say, to blowup a building.
In the raid on Trabelsi's apartment, sources say police recovered an automatic pistol and communication, detailed plans of the American embassy in Paris, chemical formula for bombmaking, and a smart business suit.
(on camera): Intelligence sources say Trabelsi was planning to attack the U.S. embassy in Paris, stuffing explosives to himself as a human bomb. The smart business suit providing him with the perfect cover.
(voice-over): French anti-terror magistrate Jean Louis Bruguiere, sources say, was quick to act on the information Beghal had given authorities in Dubai. On the tenth of September, the day before attacks in the United States, he formally ordered a team to begin surveillance on another group of suspected terrorists, living in Paris suburb of Kobet-Esson (ph).
Police say the alleged cell leader was 23-year old, Kamal Doddy (ph), a gifted computer student. The police say he with also trained in bombmaking. Investigative sources say several days after the U.S. attacks, French surveillance officers overheard members of the cell discussing the destruction of computer equipment and other evidence. Police decided to move in, and on the 21st of September arrested 7 men.
But Doddy (ph) himself escaped to Britain, captured there the following week. He was extradited to France for questioning by the investigating magistrate. With Doddy (ph) and Beghal in custody in France and Trabelsi held in Belgium, European police believe they hold some of the key players in what may have been a planned second wave of terror attacks in Europe.
BAY: Suspected terrorist cells forwarded in Europe. Signals read. Dots connected. That was not the case leading up to September 11. And there were opportunities. Coming up, the messages missed that might have helped prevent tragedy.
BAY: The attacks on the World Trade Center and Pentagon took America by surprise. But could the tragedies have been prevented? In the days leading up to September 11, there were signals. But our intelligence community just didn't put it all together. And by the time they had, it was to late.
The missed opportunities of September 11 from CNN's Mike Boettcher.
MIKE BOETTCHER, CNN CORRESPONDENT (voice-over): Noise, the bits and pieces of information transmitted through the air, moving over the Internet, spoken person to person, intercepted by satellites, cyber- snooper and shadowy spies and informants, fragmented, sketchy, and usually incomplete. There is one constant that intelligence analysts recognized before a terrorist attack. The noise level increases dramatically.
And the volume was rising before September 11. There were little clues and big hints. But were they enough to sound a loud warning? Hindsight says yes. But that's the advantage of hindsight.
The first clue came years ago in 1995, discovered after a small apartment fire in Manila, Philippines. Evidence found there led investigators to the hideout of Ramzi Youssef, the man convicted of planning the first World Trade Center bombing in 1993. Youssef had already fled, but agents did catch his right hand man, Abdul Hakim Marad. He was a trained pilot.
AVELINO RAZON, PHILIPPINE NATIONAL POLICE: He was principally recruited by Youssef's group and bin Laden's group to undertake a suicide mission.
UNIDENTIFIED MALE: What he narrated to us about a plan by the cell in the continental U.S. to hijack a commercial plane and ram it into the CIA headquarters in Langley, Virginia and also the Pentagon.
BOETTCHER: And they found more evidence, pointing to other targets, evidence the Philippine government says it passed on to the U.S.
RIGOBERTO TIGLAO, PHILIPPINE PRESIDENTIAL SPOKESPERSON: The targets they listed were CIA headquarters, Pentagon, TransAmerica, Sears and the World Trade Center. BOETTCHER: A year earlier, another clue to possible future terrorist actions. An Algerian terrorist group with ties to Osama bin Laden was already trying to make Youssef's dream a reality. Members of the armed Islamic group hijack an Air France jet in Algiers, order it flown to Marseilles, France for refueling and plan to fly it into the Eiffel Tower.
The operation is thwarted when French commandos storm the plane.
MICHAEL CHERKASKY, SECURITY EXPERT: There wasn't the acceptance of the real and present danger that al Qaeda had as to their use of airplanes, as to their continued use of truck bombs.
BOETTCHER: And there were even fresher trails to follow, too. The leaders of the world's strongest nations, known as the G-8, were targets of another bin Laden plot number this summer.
At a meeting in Genoa, the G-8 leaders, including President Bush, were to be killed by terrorists using a plane stuffed with explosives. Egyptian intelligence uncovered the plot and the summit went on, under extremely tight security.
There was noise heard closer to home as well. It was emanating from flight schools. On August 17, this man, Zacharias Mussaoui, a French citizen of north African descent, is arrested after instructors at a Minnesota flight school tip authorities to Mussauoi's strange request. He wanted to learn to fly a jet aircraft, but didn't care about instruction in takeoffs and landings.
He is held on immigration charges. But with only suspicions and no hard evidence, linking him to al-Qaeda, the FBI's Minneapolis office is denied authority to conduct clandestine searches and wiretaps in the case.
ROBERT MUELLER, FBI DIRECTOR: When it was looked at, there was insufficient probable cause, clear insufficient probable cause.
BOETTCHER: After the September 11 attacks, they do get that authority and discover that Mussaoui had a keen interest in crop dusting aircraft.
Another missed opportunity. In late August, two men who would within weeks be named as suspected hijackers of the jetliner that crashed into the Pentagon, were placed on an immigration watch list, barring their entry in the United States.
U.S. authorities became suspicious of the two, after learning about a meeting between one of them and the suspected al-Qaeda operative a year and half before in Kuala Lumpur. At the CIA's urging, both men were added to the immigration watch list, but U.S. authorities did not know Khalid al-Midar and Nawaf al-Hazmi had already entered the country by the time the warning was issued.
And while the warning reached the immigration officials too late, it was never passed to the Federal Aviation Administration, so airlines could watch for the names on U.S. domestic flights. KENNETH QUINN, FAA: Quite often, we knew of a threat somewhere out in the world, somewhere out in the field. And the either agency had it or the bureau had it, but the FAA did not.
BOETTCHER: Then there was the noise, a lot of it, heard on the streets in the Middle East last summer from those returning from al- Qaeda training camps. Peter Bergen is a leading expert on bin Laden. And Bergen's contacts in the Arab world are extensive. The gossip, he says, was everywhere for U.S. authorities to hear.
PETER BERGEN, CNN TERRORISM ANALYST: According to a source familiar with the bin Laden organization, men returning from Afghanistan, who had trained with bin Laden, arrived in Saudi Arabia in recent weeks and were talking about some kind of big operation that was imminent.
BOETTCHER: There was indeed much noise, a cacophony of sound that know one was able to hear as a coherent message until September 11.
BAY: Learning from the mistakes of the past and looking to the future. Coming up, where might terrorists strike next come and are we prepared?
BAY: America today is a changed nation. For many, the threat of another terrorist attack is not a question of if, but when and where. As investigators race to find answers to the recent wave of anthrax terror, we'll look at what investigators are targeting now.
Here's CNN's Susan Candiotti.
SUSAN CANDIOTTI, CNN CORRESPONDENT (voice-over): Since September 11, Americans have been put on alert.
JOHN ASHCROFT, ATTORNEY GENERAL: We remain in a situation where there is a significant threat of additional terrorist activity in the United States.
CANDIOTTI: Already, cases of anthrax under investigation. What could happen next? And where? Post offices, monuments, power plants, airports, and sea ports, skyscrapers, wherever large crowds gather, all possible targets where security is no longer taken for granted.
(on camera): Investigators are trying to ward off more attacks by dissecting the terrorists' plan for September 11, looking for patterns, methods, associates, that could reveal what else terrorists had in mind.
DONNA BUCELLA, FMR. JUSTICE DEPT. OFFICIAL: Perhaps we will do more substance than form now. CANDIOTTI: Former Justice Department official Donna Bucella.
BUCELLA: We look a little closer at people we hire. We look a close or at people who have certain security clearances. We look a little closer at people taking flight lessons and learning how to, you know, turn planes and not worry about flying up and down. We take a closer look at crop dusting.
CANDIOTTI: After discovering a crop dusting manual in the possession of a man now held as a material witness, the FBI searched airfields nationwide.
RAY DYSON, SOUTHEAST AERIAL CROP SERVICE: Just in case someone should try to steal the airplane, we've locked the prop so that they can't turn.
CANDIOTTI: The FBI is canvassing every flight school, searching records for possible associates. Schools which unwittingly taught hijackers blame immigration loopholes for allowing potential terrorists to slip in and out of the country.
RUDI DEKKETIS, PRESIDENT, HULLMAN AVIATION: A background check on foreigner can take four to six weeks. How the hell do we do that? That's not possible.
UNIDENTIFIED MALE: If you would go ahead, open the back up. Let's check your securement of your load.
CANDIOTTI: Fear over truck bombs now driving the FBI to examine that industry under the microscope. Tips about suspicious students cropping up nationwide. Roadside and border checks are on the rise, but how many trucks realistically can be screened?
RANDY HUMPHREY, TRUCK DRIVER: I went to Texas with this here load that I took down on this trip. I had a hazardous load on. And I didn't get checked.
CANDIOTTI: In 1995, no one discovered a truck filled with fertilizer and racing fuel before it killed 168 people in Oklahoma City. Strict regulations on fertilizer sales followed. Now fertilizer companies put on notice again. Know your customers.
JOHN FREDERICK, FERTILIZER & CHEMICAL MANUFACTURER: It's personal responsibility everyday, everyone getting up and being aware of the possibility of things.
CANDIOTTI: Taking no chances within hours of the attacks, security at all nuclear power plants jumped to the highest level.
REP. ILEANA ROS-LEHTINEN (R), FLORIDA: They are now doing more background screening than ever of all of their employees. They're making sure that the caterer, the janitors, anyone who has any access to this facility has been totally cleared.
CANDIOTTI: A government web site that features extensive information about nuclear power was temporarily shut down to remove details, including plant design and latitude and longitude. Investigators also sifting through computer e-mails, to find out how terrorists used the Internet to communicate.
For the FBI, an avalanche of information.
JIM DEMPSEY, CENTER FOR DEMOCRACY AND TECHNOLOGY: The most troubling problem is terrorist or criminal who doesn't use the new technology, the person who operates only in cash and communicates only face-to-face. That's where the intelligence agencies are really in the dark.
CANDIOTTI: And unsettling prospect, especially if sleeper agents are lying in wait, having learned from their predecessors how easy it can be to hide in plain sight.
BAY: The investigation into the terrorist attacks on America continues. And investigators do seem to learn more and more everyday. As additional pieces are added to the puzzle, we should get a better idea of what has happened and of what might happen next.
That's this edition of CNN PRESENTS. I'm Willow Bay. Thanks for joining us.
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