WASHINGTON — The FBI in the past decade has tripled its spending to stop terrorism, quintupled the number of intelligence gatherers and revamped its bureaucracy to share information about terrorists across the government.

None of it was enough to stop the deadliest terrorist attack in U.S. history.

Long before Sept. 11, the urgency was growing: In the past two years, the CIA cabled to the FBI names of about 100 suspected associates of Osama bin Laden thought to be bound for or already in the United States. An Aug. 23 cable bore the names of two, Khalid al-Midhar and Nawaq Alhazmi. The FBI sought the men, but failed to locate them before they boarded the airliner that crashed into the Pentagon.

The attacks in Washington, D.C., and New York found the nation's chief domestic law-enforcement agency ill-equipped and unprepared. An agency that must track terrorists who rely heavily on technology lacks computers that can quickly access the Internet. Boxes of evidence have piled up in previous terrorist plots, but the FBI hasn't had translators to decipher them. It lacks Arab agents who can penetrate terrorist cells and has too few veterans who see connections among foreign suspects and far-flung sites.

These weaknesses persist, officials say, despite the 1998 decision by Louis Freeh, director at the time, to make terrorism a top agency priority. FBI counterterrorism spending grew to $423 million by 2001. The goal, spokesman John Collingwood said, was to move "from a reactive to proactive posture," not just gathering intelligence but using it to anticipate and plan for a variety of threats.

"We started down this road, but we didn't move as fast as the terrorists," said Jamie Gorelick, former No. 2 to Attorney General Janet Reno.

FBI officials say the agency is vastly better prepared than it was five years ago, citing a string of successful prosecutions, most recently in the bombings of U.S. embassies in Kenya and Tanzania. Other planned attacks were thwarted, Collingwood said.

Failure to track suspects

Current and former officials say, however, that the FBI has always been at its best in making cases against known criminals. The Sept. 11 tragedy shows more basic problems, authorities say.

"There were some people whose activities should have been tracked and they weren't," said Michele Flournoy, a security adviser for the nonprofit Center for Strategic and International Studies.

Communications among U.S. intelligence agencies, particularly the FBI and CIA, have always been a problem, cited as recently as last year in a report by the congressionally appointed National Commission on Terrorism. The report faulted the FBI for slowness in disseminating "terrorist information that may not relate to an immediate threat."

Even when it had information, the report said, the FBI sometimes did not know what to make of it. One reason, the report said, was investigators "lack the training or time to make such assessments."

A series of events and specific alerts in the weeks before Sept. 11 did not sound an alarm within the agency that a threat was building, interviews show.

Since 1996, the FBI had been developing evidence that international terrorists were using U.S. flight schools to learn to fly jumbo jets. A foiled plot in Manila to blow up U.S. airliners and later court testimony by an associate of bin Laden's had touched off FBI inquiries at several schools, officials say.

But alarms were not tripped when in mid-August, the owners of a Minnesota flight school alerted the FBI to a man who paid cash to use flight simulators to learn how to fly passenger jets.

The man, Zacarias Moussaoui, was held in a local jail on federal immigration violations, and the FBI says it passed along information about the arrest to other law-enforcement agencies. That netted some results: By Sept. 1, French intelligence notified the FBI that Moussaoui was a "radical Islamic extremist" with possible ties to Afghan terrorist training camps.

The FBI still did not take him into federal custody. Now, authorities are trying to determine whether Moussaoui sought flight training to be part of the hijackings. He is being held as a material witness.

The agency's inability to find al-Midhar and Alhazmi illustrates that even improved communication with the CIA does not guarantee swift action — or success. On Aug. 23, the CIA cabled the FBI and other agencies that they should be on alert for two men with possible links to terrorists. Al-Midhar had been videotaped months earlier meeting with a suspect in the bombing of the USS Cole, and the CIA advisory was "not a routine matter," an official familiar with the events said.

The Immigration and Naturalization Service (INS) confirmed the men were in the United States and the FBI launched a search. But stymied by false addresses, agents concentrated on New York and Los Angeles. They did not make it to San Diego, where the suspects had been living, until after the hijackings.

FBI officials contend that without more specific information and sources within the terrorist cells, it would have been impossible to thwart the Sept. 11 attacks.

"It is much easier to penetrate the Gambino crime family than the bin Laden crime family," a senior government official said. The growth of bin Laden's terrorist network and its suspected attacks on U.S. targets have brought vexing challenges to the FBI: understanding Arabic, recruiting agents who can blend into foreign cultures and quickly deciphering obscure information.

Evidence wasn't translated

The limitations became apparent as early as 1993, when a loosely organized Islamic group planted a bomb under the World Trade Center. When they began building cases against the men, agents discovered to their dismay that some elements of the plot had been outlined in handwritten Arabic documents collected three years earlier in the murder case of Rabbi Meir Kahane. The documents included photos and schematic drawings, but the material was not translated or analyzed.

The problem was still urgent last year after Freeh appealed to Congress for $5 million for translation services: "The FBI has not been able to translate all of the recorded audio conversations and documents it has obtained during investigations."

Last week FBI Director Robert Mueller cited a "critical need" for translators as he pleaded for help from Americans fluent in Arabic, Farsi and Pashto. The bureau has been flooded with applicants, who must undergo background checks to ensure an undercover terrorist, or "mole," does not burrow into the agency.

The FBI also is hampered by a scarcity of Arab-American agents, said Robert Blitzer, former FBI chief of domestic counterterrorism. He estimated the number at no more than 25.

"If you don't have an Arab-American agent on your staff, how the hell do you recruit Arabs?" Blitzer said. "You don't even understand the culture."

In 1995, the FBI began adding hundreds of counterterrorism agents. But funding for computers, secretaries and support service lagged.

FBI translators need more than language skills. Law-enforcement sensibilities and an ability to decipher street jargon are critical. In a 1993 investigation in New York, conspirators referred to bombs as hadduta, which literally translated means a child's bedtime story, the FBI said.

"Wiretaps do you no good if you have no one who can translate, or can be able to understand what they are hearing," said Peter Probst, a former terrorism expert for the Defense Department and the CIA.

A badge and a laptop — those were the tools former director Freeh said all his new agents would carry to demonstrate their technical proficiency.

In fact, for several years under Freeh, agents leaving the training academy did go out the door with a computer. But recently the program was stopped because it was not cost-efficient.

More than 13,000 FBI computers are four to eight years old, meaning they cannot run today's basic software or allow agents to move to different functions with a mouse.

"The productivity loss and frustration that result are enormous," the FBI's Bob Dies told a Senate panel in July. Dies is assistant director of the information resources division.

Most smaller FBI offices have low-speed Internet access, and agents cannot electronically store photographs, graphics and charts, Dies said. Some sensitive classified and criminal data are available only on paper.

A $242 million, three-year plan to upgrade FBI systems is under way, but "at the dawn of the 21st century, the FBI is asking its agents and support personnel to do their jobs without the tools other companies use or that you may use at home," Dies testified.

Personnel challenges

Personnel challenges, such as retaining the most experienced agents and upgrading the quality of FBI analysts, also remain an issue. "They've got a lot of personnel problems which they have been trying to turn around and deal with in the last five or six years," said Nancy Savage, a 24-year FBI veteran who now works in Portland and heads the FBI Agents Association, a professional organization.

While some investigators have long track records working with terrorism, nearly half the FBI's agents were hired since 1993, after the first World Trade Center bombing.

Many FBI analysts, who assemble and divine patterns in mountains of intelligence, were hired before 1993, years before the FBI tightened educational requirements for those jobs.

"There is a caste system in the FBI that for a long time placed more value on the agents who collect information than on the non-agent analysts who have to put the pieces together," a former FBI administrator said.

And without a crisis, it can be tough to get analysts working on "threat assessment," which is supposed to be one of their functions, Savage said. In the FBI's local offices, analysts "get pulled to do all sorts of things: night shifts answering phones, anything that might be administrative."

"You can't recognize patterns unless you gather information to establish some standard of behavior and then, how do you notice a pattern if you don't have experience?" said terrorism specialist Martha Crenshaw, a professor of government at Wesleyan University.

Within the bureau, the priority is on making arrests, which are rare in terrorism cases. Agents assigned to white-collar crime and drug cases accumulate better track records.

And FBI agents told the congressional terrorism commission that the Justice Department has made the process of wiretapping terrorist suspects "slow and burdensome." That sentiment was echoed in a July report by the General Accounting Office, the auditing division of Congress. In the past week, the Bush administration has called for broader wiretapping authority for investigators, one of a series of proposed reforms to make it easier to track suspects.

A tougher challenge will be using the Sept. 11 tragedy to redefine the FBI's objectives and mission.

Gorelick, Reno's former deputy, foresees a radical restructuring. Narcotics cases might be handed off to the Drug Enforcement Administration; white-collar crimes to state and local authorities.

That way, she said, the FBI could focus on terrorism — with a goal of pre-empting attacks.

"They can surge when something bad happens, like now," Gorelick said. "But as a sustained matter, they're not there."