To this day, the precise reach of his power remains unknown: how many members Al Qaeda could truly count on, how many countries its cells had penetrated — and whether, as Bin Laden had boasted, he was seeking chemical, biological and nuclear weapons.

He waged holy war with modern methods. He sent fatwas — religious decrees — by fax and declared war on Americans in an e-mail beamed by satellite around the world. Qaeda members kept bomb-making manuals on CDs and communicated through encrypted memos on laptops, leading one American official to declare that Bin Laden possessed better communications technology than the United States. He railed against globalization, even as his agents in Europe and North America took advantage of a globalized world to carry out their attacks, insinuating themselves into the very Western culture he despised.

He styled himself a Muslim ascetic, a billionaire’s son who gave up a life of privilege for the cause. But he was media savvy and acutely image-conscious. Before a CNN crew that interviewed him in 1997 was allowed to leave, his media advisers insisted on editing out unflattering shots. He summoned reporters to a cave in Afghanistan when he needed to get his message out, but like the most controlling of C.E.O.’s he insisted on receiving written questions in advance.

His reedy voice seemed to belie the warrior image he cultivated, a man whose constant companion was a Kalashnikov rifle that he boasted he had taken from a Russian soldier he had killed. The world’s most threatening terrorist, he was also known to submit to dressings down by his mother. While he built his reputation on his combat experience against Soviet troops in Afghanistan in the 1980s, even some of his supporters questioned whether he had actually fought.

And though he claimed to follow the purest form of Islam, many scholars insisted that he was glossing over the faith’s edicts against killing innocents and civilians. Islam draws boundaries on where and why holy war can be waged; Bin Laden declared the entire world as fair territory.

Yet it was the United States, Bin Laden insisted, that was guilty of a double standard.

“It wants to occupy our countries, steal our resources, impose agents on us to rule us and then wants us to agree to all this,” he told CNN in the 1997 interview. “If we refuse to do so, it says we are terrorists. When Palestinian children throw stones against the Israeli occupation, the U.S. says they are terrorists. Whereas when Israel bombed the United Nations building in Lebanon while it was full of children and women, the U.S. stopped any plan to condemn Israel. At the same time that they condemn any Muslim who calls for his rights, they receive the top official of the Irish Republican Army at the White House as a political leader. Wherever we look, we find the U.S. as the leader of terrorism and crime in the world.”