In U.S., Terrorism's Peril Undiminished

* There are at least two important disagreements among the officials interviewed for this story, one of fact and one of policy. They have no consensus on whether al Qaeda is replacing its top operatives with competent successors as fast as it loses them, which has important implications for the success of the president's strategy. And they do not agree on how soon, and with how much priority, U.S. policy should turn to addressing sources of grievance in the Arab and Islamic worlds -- a difference that leads them to different views on whether the war on al Qaeda will be enhanced or set back by war against Iraq.

The gravest risks from al Qaeda combine its affinity for big targets and its announced desire for weapons of mass destruction.

"Most sobering to me was their research on chemical weapons, radiological dispersion devices, and their fascination with nuclear weapons," said Downing, who granted no interviews during his White House tenure and had not spoken about it until now. "They are obsessed with them."

Terrorism in its latest form has brought home the paradox of "asymmetric war," in which even a powerful nation may be badly hurt by an antagonist of incomparably lesser strength. But the fight with al Qaeda has a symmetry as well. Bush wants to kill al Qaeda from the top, and much the same describes al Qaeda's plan for the United States.

In an interview conducted in June but broadcast in September by the satellite television network al-Jazeera, al Qaeda operative Ramzi Binalshibh said United Flight 93, which crashed in Pennsylvania on Sept. 11, had been aimed at Congress.

U.S. analysts lean to the view that Binalshibh was lying. Four officials said the better evidence points to the White House as the target.

Downing declined to address intelligence questions, but he stated an observation that was also made by currently serving officials on condition that their names not be published. Al Qaeda returned on Sept. 11, 2001, to the World Trade Center, which allied terrorists nearly succeeded in toppling in a 1993 bombing. It failed, then succeeded, in attempts to kill an American diplomat in Amman, Jordan. And after missing the USS The Sullivans in port in Yemen in January 2000, he noted, al Qaeda mounted an identical attack with an explosives-laden boat -- this time successful -- against the USS Cole eight months later.

"These guys continue to go back after targets they have tried to get before," Downing said. "That's why I expect they're going to go back to Washington and why I expect they're going to go back to New York, both because of the symbolic impact of those attacks and the economic effect."

The strongest expression of that view came in very personal terms from a participant in efforts against al Qaeda whose office is adjacent to Pennsylvania Avenue.

"They are going to kill the White House," the official said. "I have really begun to ask myself whether I want to continue to get up every day and come to work on this block."

Among all the upheavals of war with al Qaeda, the surest indicator of the historic stakes is the ongoing rotation of top U.S. government managers -- scores at a time -- into a bunker deep underground and far from Washington. No president before Bush considered the "continuity of government" to be in doubt or took the costly step of maintaining a permanent presence under shelter.

Those who serve weary tours there describe the experience as surreal -- "pretty cool for about an hour," one said, "but then very, very sobering." Among the sobering features, more than one of them said, is recognition that vital elements of constitutional authority are still at risk, even if planners have foreseen enough to provide for all the eventualities of a catastrophic attack.