"The steady growth of Osama bin Laden's anti-U.S. sentiment through the wider Sunni (Islamic) extremist movement, and the broad dissemination of al Qaeda's destructive expertise, ensure that a serious threat will remain for the foreseeable future — with or without al Qaeda in the picture," Tenet told the Senate Intelligence Committee in his annual assessment of global threats.
The leadership of the original al Qaeda terror group, which the United States targeted after the Sept. 11, 2001, attacks, is seriously damaged, Tenet said. Beyond al Qaeda however, Tenet said, there is a continuing threat to the United States from a "global movement infected by al Qaeda's radical agenda."
"And what we've learned continues to validate my deepest concern — that this enemy remains intent on obtaining and using catastrophic weapons," he said.
Tenet named an array of groups that are taking up al Qaeda's fight: Ansar al-Islam in Iraq, the Libyan Islamic Fighting Group, the Islamic Movement of Uzbekistan, and Morocco's Salifiya Jihadia.
Hours before Tenet spoke, an audiotape purportedly from an al Qaeda leader, denied U.S. claims that the terrorist group was weakened.
Portions of separate audiotapes attributed to Ayman al-Zawahri were broadcast a few hours apart on Al-Arabiya and Al-Jazeera, competing pan-Arab satellite channels based in the Persian Gulf.
"We remind Bush that situation is not stable in Afghanistan, or else how do we wage, with God's support and might, our attacks on your troops and agents. … How do we send our messages that challenge you and reveal your lies," the tape said.
"We remind Bush that he didn't destroy two-thirds of al Qaeda. On the contrary, thanks be to God, al Qaeda is still in the holy war battleground raising the banner of Islam in the face of the Zionist-Crusader campaign against the Islamic community," it added.
FBI Director Robert Mueller told the committee that the Olympic Games in Greece and the Democratic and Republican presidential nominating conventions are among the FBI's top security concerns this year.
The public session comes after months of scrutiny of the intelligence community's pre-war and so-far faulty estimates that weapons of mass destruction would be found in Iraq.
"The question I am wrestling with is whether in fact we are as a country and as a people safer today than we were when the three of you were here a year ago," Sen. Jay Rockefeller said in opening statements, speaking to Tenet, Mueller and the director of the Defense Intelligence Agency.
Security in Iraq remains elusive and "we're paying a very high price in blood and resources … and in world opinion," Rockefeller said of the U.S. decision to invade Iraq without more international support
While members of the Bush administration caution that the search in Iraq is not over, the debate heated up in last month when Tenet's former special adviser, David Kay, left his position as the top U.S. weapons inspector in Iraq. Kay began saying publicly that he doesn't believe weapons of mass destruction will be found.
The hearing comes as officials continue to examine the performance of intelligence agencies on an array of fronts.
For example, the federal commission reviewing the Sept. 11 attacks is looking into whether the United States failed to aggressively track one of the 2001 hijackers after obtaining his first name and phone number from German authorities more than two years before the attacks.
The New York Times, in its Tuesday editions, quoted German intelligence officials who said they had given the CIA the first name and telephone number of Marwan al-Shehhi, and asked U.S. officials to track him. The Germans said they never heard back from U.S. officials until after Sept. 11.
Al-Shehhi was the hijacker who took the controls of United Airlines Flight 175, which flew into the south tower of the World Trade Center.
A U.S. official told The Associated Press late Monday that thousands of full names of suspected terrorists come across the intelligence community's screens on a regular basis, making them hard to always track.
Meanwhile, a presidential commission is probing the quality of intelligence on Iraq, Iran, Libya and other countries. The House and Senate intelligence committees are investigating Iraq intelligence, as are both an internal and independent CIA probe.
Separately, the FBI is probing the origin of forged documents that were believed to be evidence that Iraq tried to obtain uranium in Africa; the documents were shown to be fakes, and the allegation against Iraq has been withdrawn.
And in a related investigation, the Justice Department is trying to find out who leaked the name of a CIA operative to reporters. The leak, which may have violated federal law, came after the operative's husband criticized the Bush administration's case for war.