It sounds like the plot from a Tom Clancy thriller, or some far-fetched action film starring Bruce Willis or Arnold Schwarzenegger.
A team of terrorists hijacks four American jetliners loaded with passengers. They turn the planes into guided missiles, crashing two of them into the World Trade Center, and one into the Pentagon.
After an apparent act of great heroism by a few passengers, the fourth aircraft crashes prematurely into a wooded area in Pennsylvania. But by that time, the damage is done. About 5,000 people are presumed dead.
Astonished Americans are still asking: How could it happen?
How could a handful of men armed only with knives and box-cutters bring the world's most powerful nation to its knees without firing a shot?
Experts on terrorism are not surprised by these events. Some are surprised that it didn't happen much sooner.
"I'm surprised by the magnitude of what happened, but I'm not surprised that it happened," said Robert Heibel, former FBI deputy chief of counterterrorism. "The messages and warnings have been coming for the past 10 years."
Clancy is a best-selling novelist known for his comprehensive research and accurate portrayals of the military and intelligence communities. His 1994 book, "Debt of Honor," tells of an airliner that is
crashed by a suicide pilot into the U.S. Capitol.
The writer was sipping coffee Tuesday morning at the kitchen table of his Maryland home. As he watched television with millions of other Americans, it pained Clancy to see the unfolding events that could have come from one of his techno-thrillers.
"At first I thought it was a horrible accident, but then when the second building was hit, I knew it wasn't," Clancy said.
Clancy lays much of the blame on cutbacks in federal funding that have made it difficult for U.S. intelligence-gathering agencies to hire spies and informants in the Middle East and elsewhere.
"Human intelligence (from spies and informants) has been gutted for more than 20 years, and I've been screaming about this," the writer said.
Hijackers' tactics outlined
No one knows exactly what happened aboard the four doomed flights that took off from Boston, Washington and Newark, N.J. But Heibel, who retired from counterterrorism work in 1987 and now teaches courses on terrorism and intelligence-gathering at Mercyhurst College in Erie, Pa., said he can envision a likely scenario.
He believes that at least some of the terrorists dressed for their flights as prosperous businessmen, to attract as little attention as possible. Some of the terrorists probably colored their hair, he said, and investigators have recovered hair dye among the belongings of some of those suspected in the case.
"They worked in teams of three to six men," Heibel said. "I believe they had some men in the front, as close as possible to the cockpit. The others would be toward the back.
"Shortly after the plane takes off, one of the men in back grabs somebody -- a passenger or a stewardess -- and slashes their throat. People start screaming for help. Then, a stewardess goes up to the cockpit and alerts the pilots. One of the pilots opens the cockpit door, and the terrorists in the front section of the plane go into the cockpit and take over the plane. All this happens in maybe a minute or two."
The pilots were killed, incapacitated or moved to the rear of the airliner, Heibel believes. The terrorists then took hostages -- most likely women or children, with knives held to their throats -- and also told passengers that they had a bomb on board.
Passengers, fearing for their lives and unaware that the terrorists were on a suicide mission, would likely cooperate, Heibel said. He noted that the passengers who apparently fought with terrorists on the plane that crashed in Pennsylvania had learned from cellular telephone conversations that two planes had already crashed into the World Trade Center.
Need seen for sky marshals
Some critics of America's security procedures have suggested that federal sky marshals -- plainclothes officers armed with guns and specially trained to combat air piracy -- could have prevented many of the deaths of last week.
Former sky marshal Roger Childers agreed. Childers, of Minneapolis, is a retired FBI agent who served as a sky marshal in the 1970s. The marshals, in teams of at least two officers, were put aboard some flights to prevent terrorist acts.
Childers said that he does not know whether sky marshals could have saved all the passengers and crew members but that he is certain they could have prevented hijackers from crashing into the World Trade Center or the Pentagon. Childers noted that sky marshals are armed with guns, while the terrorists in this case had knives and box-cutters.
"I know what I would have done. When they took a hostage, I would have sat in my seat, waiting for the right moment. Then I would have come up behind one of them, put my gun behind his ear and shot him," he said. "Those were our instructions."
Israel's El Al airline, considered the world's most security-conscious passenger carrier, uses armed marshals on all its flights. No El Al plane with sky marshals has been successfully hijacked.
Sky marshals were used briefly in the 1970s. The program was restarted in 1985, after some overseas hijackings occurred. The Federal Aviation Administration said last year that the marshals are still in use, but only on an undisclosed number of international flights.
Since last Tuesday's suicide hijackings, Federal Aviation Administration officials said they have begun using sky marshals on domestic flights. U.S. Transportation Secretary Norman T. Mineta also has asked the Defense Department to detail some members of its elite counterterrorism unit, Delta Force, for use as sky marshals.
"I definitely support an upgrade in our use of the sky marshals," said Rep. Thomas M. Reynolds, R-Clarence, who toured the World Trade Center wreckage with President Bush on Friday.
"I don't think we'll have sky marshals on every plane, but I do think there will be a much higher probability of sky marshals than we have now."
That is a step in the right direction, Heibel said, but America's commercial airliners also need to do other things to isolate pilots from potential terrorists in the passenger sections.
"They need cockpit doors that are bulletproof and locked during the flights, and they need a camera system that allows the pilots to observe what is going on in the passenger sections," Heibel said. "We need to eliminate the need for pilots to leave the cockpit to check on passengers."
Eugene Haines, a retired American Airlines pilot who operates a flight school in Orleans County, said many pilots are uncomfortable about having armed sky marshals on their flights. But for the next few months, at least, Haines supports the use of sky marshals. "I think the real place to stop air terrorism, though, is at the passenger gates," he said.
'Whole process scares me'
Terrorism experts say the cursory examinations of passengers now conducted at American airports should be replaced by more stringent procedures, again based on the model of El Al in Israel. Passengers boarding El Al planes are physically searched and subjected to intense questioning by security officers. Luggage is searched closely.
Experts say the situation calls for improved metal detectors, and better training and pay for the workers who screen passengers at the gates.
Many checkpoint security workers make little more than minimum wage. An Atlanta-based company, Argenbright Security, pleaded guilty last year to federal charges that it allowed 1,300 untrained workers -- including dozens of criminals -- to work at checkpoints in Philadelphia International Airport.
Argenbright provides checkpoint security at the three airports where terrorists boarded jetliners last Tuesday morning. Officials at Buffalo Niagara International Airport said Argenbright does not operate the checkpoints there. Argenbright officials could not be reached to comment.
Lawrence Ramunno, a Buffalo police patrol chief, said he has worried for years about airport security. He said his heavy metal police badge is often not spotted by metal detectors when he goes through passenger gates.
"What kind of security is it when you go to an airport and they ask, 'Did you pack your luggage, and has it been out of your control?' " Ramunno said. "By answering those two questions, you can board a plane. The whole process scares me."
There is little doubt that the threat of terrorism is going to force changes that will cut back on the freedom and convenience of American lifestyles, according to John P. Keenan, a terrorism researcher who is director of leadership programs at Medaille College.
"Our mind-set in this country has always been, 'It can't happen here,' " Keenan said. "We can't have that mind-set anymore. I see these events moving us toward a different level of security. We're going to have to move toward what they have in Israel."
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