It has been a difficult week for one of America's most revered crime-fighting institutions, the Federal Bureau of Investigation. Even as FBI Director Robert Mueller announced a massive reorganization plan to focus on counter-terrorism, he acknowledged that the FBI failed to follow up on warning signs of an attack prior to September 11.

In the 1950s and 1960s, television and movies depicted FBI agents as clean-cut crusaders for law and order, tracking down gangsters and communist spies with equal fervor.

But the FBI had a dark side as well. Under the leadership of the legendary J. Edgar Hoover, the FBI launched a covert campaign of spying on American dissidents.

Commentator Joseph From recalled the FBI's excesses on VOA's Issues in the News program.

"After all, in 1972, they had to impose all kinds of restraints on it because it was engaged in domestic espionage against Martin Luther King and the civil rights movement," he said. "And it got to be an organization that worried people, particularly under [former Director] J. Edgar Hoover. Then it just got to be more and more incompetent."

Fair enough says former FBI counter terrorism chief Buck Revell. But he also says the bureau does not get enough credit for foiling about 40 terrorist attacks over the past several years.

"The intelligence services and the law enforcement agencies are today's front line troops in the war on terrorism," he said. "They are locked up 24 hours a day, seven days a week trying to prevent acts of terrorism against American citizens in the United States and abroad. And for there to be the kind of commentary coming from Senators and Congressmen that haven't got the facts and are making premature judgments, I think is very disconcerting and certainly has an adverse impact."

In the wake of September 11, the FBI has initiated a major restructuring that makes preventing terrorist attacks its top priority. But even as Director Mueller announced the new shift in focus, he readily acknowledged that FBI headquarters ignored tips and warnings from field agents about suspicious activity in the weeks leading up to the attacks on New York and Washington.

"What we need to do better is be predictive. We have to be proactive," he said. "We have to develop the capability to anticipate attacks. We have to develop the capability of looking around corners and that is the change, that is the shift in focus, particularly at headquarters."

For now, Mr. Mueller appears secure in his job. But that could change depending on what comes out of congressional hearings to be held in the weeks to come.

"Bob Mueller, who is liked and respected by the White House, basically decided that he had to just basically admit all and confess all and basically try to say that it really didn't happen on my watch," said Tom Defrank, Washington Bureau Chief of The New York Daily News and a guest on VOA's Issues in the News program. "But the problem for the Bush Administration is that it did happen on their watch, September 11th. And so I think Mueller is being bureaucratically smart but I think he is also very much committed to a total overhaul of the agency, which won't be easy."

As part of the bureau's overhaul, Attorney General John Ashcroft has approved new powers that will make it easier for FBI agents to spy on suspected terrorists inside the United States by monitoring the Internet, public libraries and even religious institutions.

Civil liberties groups have denounced the new investigative guidelines as a threat to privacy rights guaranteed under the U.S. Constitution.

FBI Director Mueller now faces the daunting challenge of improving the bureau's ability to detect terrorists while at the same time assuring the public that the agency is determined not to repeat the domestic spying abuses of the Hoover era.