The statement by Vice Adm. Lowell E. Jacoby, director of the Defense Intelligence Agency, raised the stakes in the difficult transition under way in Iraq from a U.S.-dominated military occupation to an Iraqi-led government. The United States plans to hand over authority to the Iraqis by July 1.
Jacoby's remarks were part of the U.S. intelligence community's annual worldwide threat assessment. Intelligence chiefs presented a dark picture of global terrorism 2 1/2 years after President Bush declared the war against terror as the nation's top priority.
CIA Director George J. Tenet told the Senate Intelligence Committee that even though al-Qaida's leadership had been damaged, its radical agenda had infected "a global movement." He said assaults against the United States on the scale of the Sept. 11 attacks "remain within al-Qaida's reach."
"This enemy remains intent on obtaining, and using, catastrophic weapons," Tenet said, adding: "This is a learning organization that remains committed to attacking the United States, its friends and allies."
Testifying alongside Tenet and Jacoby, FBI Director Robert S. Mueller III said al-Qaida has retained a "cadre of supporters" within the United States to develop plots and carry out instructions. Mueller highlighted the case of a Baltimore resident who he said had "direct associations" with two top al-Qaida operatives now in custody.
Law enforcement sources said the statement referred to Majid Khan, a suspected operative who briefly lived in Baltimore more than a year ago and was allegedly part of a loosely developed plot to blow up gas stations. Sources said he stayed with relatives while in the city and studied the vulnerability of gas stations to bombings.
Officials believe Khan had direct contact with Khalid Shaikh Mohammed, the captured al-Qaida operations chief and alleged mastermind of the Sept. 11 attacks, but they said the gas station plot never moved past the exploratory stages.
Khan later left the country for Pakistan, where he was captured. Khan, now being held in an undisclosed location, has been cooperative with authorities, the sources said.
The intelligence community's assessment of terrorism in Iraq comes against a backdrop of continued attacks against American troops and bombings of U.S.-trained Iraqi police, and uncertainty over what kind of government will take shape after the end of the occupation.
The Bush administration has retreated from its plans to conduct regional caucuses to put together an interim government that would rule Iraq until nationwide elections can be called and is relying heavily on the United Nations to put together an alternative way to choose Iraq's leadership.
"Iraq is the latest jihad for Sunni [Muslim] extremists," Jacoby said in his prepared testimony. "Iraq has the potential to serve as a training ground for the next generation of terrorists where novice recruits develop their skills, junior operatives hone their organizational and planning capabilities, and relations mature between individuals and groups."
Such a situation, he noted, "was the case during the Soviet occupation of Afghanistan and extremist operations in the Balkans."
In the 1980s, Afghanistan became a magnet for anti-Soviet fighters throughout the Muslim world, including Osama bin Laden, who later formed al-Qaida.
The White House has claimed that the United States struck a blow against terrorism by toppling Saddam Hussein's government. The administration claims the ouster of Hussein, by opening the way for democracy in Iraq, will serve to decrease regional extremism.
Intelligence agencies have not been able to establish any close operational links between Hussein's regime and al-Qaida before the U.S.-led invasion.
Tenet said that terrorists and foreign "jihadists" coming to Iraq want to halt the development of democracy in Iraq and "hope for a Taliban-like enclave in Iraq's Sunni heartland that could be a jihadist safe haven."
"We've seen a few signs" of cooperation between these holy warriors and employees of Hussein's old regime, he said, and the intelligence community is concerned that the two separate anti-U.S. elements could coalesce.
Efforts to round up former regime figures had disrupted some insurgent plans, Tenet said. "But we know these Baathist cells are intentionally decentralized to avoid easy penetration and to prevent the roll-up of whole networks. Arms, funding and military experience are readily available."
Yesterday's hearing occurred as the U.S. intelligence community seeks to rebuild its credibility with Congress and the public after assertions about Iraq's stockpiles of weapons of mass destruction failed to be borne out during postwar searches.
In a speech Feb. 5, Tenet acknowledged that U.S. intelligence agencies had failed to penetrate the upper levels of Hussein's regime. He said yesterday that "we're going to find warts" in intelligence collection and that "discrepancies" had emerged in prewar accounts by defectors about the regime's weapons of mass destruction.
But panel members from both parties continued to press him to justify Bush's policy of launching a pre-emptive war against Iraq based on what turned out to be inadequate intelligence.
Republican Sen. Olympia J. Snow of Maine said a "mixed message" had been sent when the administration characterized the Iraqi threat as "grave" and "serious" but failed to apply the criterion contained in its own national security strategy for pre-emptive attacks - that the threat be "imminent."
Democrats ignored a request to steer clear of the weapons controversy by committee Chairman Pat Roberts, a Republican from Kansas, who noted that Tenet will testify on that subject next week.
In a heated exchange with Tenet, Democratic Sen. Richard J. Durbin of Illinois said, "We will all concede Saddam Hussein is a bad man, and I'm glad he's out of power. But many more arguments were made to the American people to justify this invasion. And it turns out that the bulk of them were just plain wrong, either bad intelligence or misleading the people."
His voice rising, Tenet defended the intelligence community's overall record. "Now, we're not perfect, but we're pretty damn good at what we do. And we care as much as you do about Iraq and whether we were right or wrong. And we're going to work through it in a way that we tell the truth as to whether we were right or wrong."
He continued: "We followed this for eight, nine, 10 years. We had deep concerns about [Hussein's] history, the deceit, what he didn't give the U.N."
Tenet said that after U.N. inspectors left Iraq in 1998, the CIA tried to resuscitate sources in the country "and the record was mixed, and we made judgments on a narrower band of data. This is a tough business."
He also acknowledged that two years before the Sept. 11 attacks, the CIA had been given the first name and telephone number of one of the hijackers. But he insisted that "we didn't sit on our hands" with the tip but had tried to learn more.
Sen. John D. Rockefeller IV, a West Virginia Democrat, disputed the contention by Tenet, Jacoby and Mueller that Americans are safer now than a year ago. He pointed to testimony by Jacoby showing a sharply negative trend throughout the Muslim world in attitudes toward the United States.
"We are deceiving our people, if we don't let them know how tough a fight this is going to be," Rockefeller said.
Sun staff writer Laura Sullivan contributed to this article.