Perhaps the most significant thing about the latest Osama bin Laden videotape is how dramatically different it is from those that came before.
This time, he's alone. His beard is splotched with more gray. The area behind him is covered - perhaps to prevent geologists from analyzing background rocks that could betray his location. And, observers say, his words and posture seem less confident and more defensive.
It all points to a man whose top lieutenants may be either dead or scattered. Besieged by the globe's most powerful military, he may be sleeping in a different place every night, eating only scraps.
Yet the very fact that he could make the tape - and deliver it to the world - also betrays a deep-seated defiance, a sophisticated media savvy, and the knowledge that if he and his cause are to survive, he needs Muslim public opinion on his side.
It also points up a political difficulty the Bush administration faces: The American public sees getting Mr. bin Laden as a chief war aim, and could grow impatient if tapes continue to appear.
"He looks pressurized - like someone who is slowly realizing the effects he originally desired are not coming to pass," says Magnus Ranstorp, deputy director of the Centre for the Study of Terrorism and Political Violence in St. Andrews, Scotland. "Yet it also shows he's still around - and that he's trying to play the propaganda card, which is the only card he has left."
The tape - which aired yesterday on the Al Jazeera Arabic-language network - was the fourth video seen in the West since the Sept. 11 attacks.
The first two also came via Al Jazeera. They showed bin Laden surrounded by aides in a cave-like setting. The third - released by American officials - was taken at a dinner in an associate's home. It showed bin Laden talking casually and confidently about the attacks of Sept. 11.
In all, the tapes indicate bin Laden's media savvy. "The guy obviously had a PR campaign planned out from the get-go, using Al Jazeera as his conduit," says John Daly, a scholar at the Middle East Institute here. He adds that the US has been somewhat flat-footed in responding to the tapes.
The new tape will likely cast some doubts on recent rumors, all unconfirmed, that bin Laden is ill or dead. It indicates that, at least as of a few weeks ago, he was alive - and defiant. In fact, says Mr. Daly, "in the ... public-relations war, Osama is still somewhat ahead of George Bush."
But some see less confidence in the new video.
"He's more animated," says Dr. Ranstorp. "He's trying to be calm, but there's a sense of desperation."
Bin Laden's invocation of sympathy for the Palestinian cause aims to rally the Muslim world against Israel and the US.
But US officials point out that in the third tape - the so-called "home video" - bin Laden didn't mention any such sympathy for the Palestinian and Iraqi causes. This, they say, proves that his mention of them on the Al Jazeera tapes is simply propaganda - and not heartfelt.
At press time yesterday, the White House hadn't decided whether to put a US official on Al Jazeera to rebut bin Laden. But clearly, Muslim public opinion is a concern.
The latest tape points out that, after two months of intense US military activity in the region, bin Laden's Al Qaeda network still exists - and has the means to make a tape, get it out of Afghanistan or Pakistan, and get it to Al Jazeera.
"The toughest thing with Al Qaeda is, we don't know how extensive the organization is, so we're not really sure how much we've disrupted it," says James Lindsay, a national security expert at the Brookings Institution here. "Have we impaired it 80 percent, 90 percent, or only 30 or 40 percent?"
This question of what constitutes success may also affect the American public's perception of the Bush administration - and how well it's doing in fighting the war on terror.
A Christian Science Monitor/TIPP poll taken last month, for instance, found 87 percent of Americans saying that if bin Laden and his top aides aren't captured or killed, the US will have failed in its primary war objective.
Given this sentiment, the Bush team needs to reinforce the idea that the war is not just against bin Laden or Al Qaeda. Otherwise, "they could find themselves in a situation where they've over-personalized the war," and lose public support, says L. Paul Bremer, head of the Marsh Crisis Consulting group here.
Indeed, in the long run, capturing or killing bin Laden won't solve underlying issues such as fundamentalism, or anti-Americanism.
Getting bin Laden, says Daly, "may end the most high-profile, transnational version of terrorism, but it doesn't address globally a lot of the reasons people are fighting to begin with."