One focus of Williams' memo is the suspected link between Arizona flight students and the radical group Al-Muhajiroun, which loosely means "The Emigres," according to several sources familiar with the memo.
Authorities in Britain long have investigated the group and its leader, Sheikh Omar Bakri Mohammad, a London-based Muslim cleric who has dubbed himself the "mouth, eyes and ears of Osama bin Laden." Those investigations focused on whether Al-Muhajiroun was one of many front organizations for Al Qaeda and whether it had engaged in any terrorist activities, including recruiting and sending young Muslim militants to Al Qaeda training camps in Afghanistan. It has openly issued calls to arms against the U.S. and its allies.
A former FBI official who recently left the bureau said that, had the Phoenix memo not hit a dead end at FBI headquarters before Sept. 11, it could have led to significant information about Al Qaeda terrorist cells within the United States, including Al-Muhajiroun supporters.
The former FBI official said Al-Muhajiroun itself was not under active investigation but that anyone associated with it had drawn FBI scrutiny because of their suspected ties to other radical organizations, including Al Qaeda.
"It is a radical group with radical ideological leanings," the former official said. "So it would be naive to think that, even if the group says it engages just in political or public relations activity, that that's all it does and that none of its members are involved in other types of logistical, financial or direct support of terrorist activity. You can be a member of Al-Muhajiroun and it would be very likely that you were a member or supporter or sympathizer of Al Qaeda."
Steven Emerson, a terrorism consultant to Congress, said the group recruits young militants in England and claims to provide them with military training there and elsewhere. Efforts to reach the group, which has a Web site filled with virulent anti-American rhetoric, were unsuccessful.
The detailed nature of the case laid out by the memo is likely to intensify questions from members of Congress about whether the intelligence community missed warning signs that could have headed off a possible attack. But Goss, who chairs the House Intelligence Committee, cautioned against any rush to judgment.
"I haven't got any smoking gun. I haven't even got a cap pistol," he said. In general, Goss said, "I have not found a single instance of omission yet where someone had something they should have sent to someone else or anything that is an obvious failure. The next question is, were the procedures in the FBI appropriate, and I can't answer that question. All those questions are going to be answered in our report" later this year.
Goss refused to discuss the substance of the briefing his panel got from Williams and the FBI but said that "our time this morning was astonishingly well spent."