An increasing number of government analysts believe Osama bin Laden is dead, but the assessment is based on rational deduction, not hard evidence.
Interviews with Bush administration officials in recent weeks show an increasing shift in opinion to the "no longer with us" column when it comes to Washington's No. 1 guessing game, "Dead or Alive?"
Only one senior official, the FBI's counterterrorism chief, has yet opined in public that bin Laden, the mastermind behind the September 11 attacks, is dead. But other top officials are said to share his view in private.
"As time goes by and we don't hear from the guy, it's natural that more people tend to think he's dead," said a senior U.S. official, who asked not to be named. "There is no new information. There are always reports, 'Elvis sightings' he might have been here or there, but nothing that would be credible."
This official said the intelligence community has received scores of reports on bin Laden's movements, but none were confirmed.
U.S. intelligence last picked up hard evidence on bin Laden in late 2001. Two things happened. First, al Qaeda, bin Laden's terrorist group, released a videotape of its leader in mid-December. The CIA determined the tape was made around that time because of references he made to contemporaneous events.
Second, the United States picked up bin Laden's voice on a short-range radio in Tora Bora, the mountainous region in northeastern Afghanistan where many al Qaeda terrorists made a last stand during intense coalition air strikes.
Since then, U.S. intelligence has not picked up one credible report on bin Laden — alive or dead. Defense Secretary Donald H. Rumsfeld says he has "not heard hide nor hair" of the Saudi exile since December.
The arguments that bin Laden is dead:
•Bin Laden has an enormous ego, and with it, a need to appear in public. His career as a terror master is replete with press conferences, interviews and homemade videotapes aired on Al Jazeera, the Arabic-language satellite station in Qatar. It is also odd that at a time when his al Qaeda operatives are on the run that bin Laden would miss a chance to go public and prop up morale.
"He has too big an ego to stay quiet this long," said a senior military officer. He added that others, including some four-star generals, share his opinion.
Added an Army officer involved in the hunt for al Qaeda terrorists, "I personally think he is dead. His ego is too big to not tweak us by sending out a video."
•It is easier to hide bin Laden's death than his life. This argument goes that if bin Laden did die in the battle of Tora Bora, it is likely that it happened with the knowledge of only a few top aides. They have steadfastly guarded their secret to keep al Qaeda terrorists from becoming dispirited.
If bin Laden were alive, he must be talking to al Qaeda members at some point, who in turn talk to other followers. Those conversations would surface in communications "chatter" and be picked up by U.S. intelligence.
The United States heavily bombed cave openings in Tora Bora, putting one to three penetrating bombs in each entrance to make sure the entire complex was destroyed. Some officials believe bin Laden and his top aide, Ayman Zawahiri, may be buried amid the limestone rubble.
•Al Qaeda supporters have put out videotapes of anti-Western speeches by bin Laden, claiming that they are new. U.S. analysts say all tapes since December are old. Some surmise that al Qaeda is putting out phony tapes to cover up bin Laden's death.
Other analysts say bin Laden may be afraid to produce a new tape because the production and delivery process could give away his location. But the counterargument is that if bin Laden's spokesman, Abu Ghaith, was able this summer to put out a contemporaneous audiotape, then his boss should be able to do the same thing.
Officially, the CIA's best assessment today is that bin Laden probably is alive and hiding somewhere in eastern Afghanistan or western Pakistan. Much of that assessment is based on two facts: There is no hard evidence bin Laden is dead, and no confirmed reports that he escaped the region.
Mr. Rumsfeld was asked Saturday by CNN whether he thought bin Laden was alive.
"I don't believe I've seen a hard piece of information that would persuade me that he was alive since last December, and it's now September," the defense chief said. "He may be alive, he may be dead, he may be injured. But I've not seen anything that persuades me that I could have high confidence with respect to any one of those three answers."
Some senior military officers believe bin Laden was wounded during the early days of the air war against al Qaeda and the Taliban regime that sheltered it in Afghanistan. He appeared tired, grayer and stressed in the December videotape. He did not move his left arm during the entire 30-minute diatribe against the West.
Dale Watson, who retired last month as the FBI's counterterrorism chief, told an audience in July that "I personally think he is probably not with us anymore, but I have no evidence to support that."