But he admitted to an audience at Georgetown University in Washington on Thursday that his agency may have been wrong about Saddam Hussein possessing nuclear weapons.
"No one told us what to say or how to say it," Tenet said. He said analysts differed on several important aspects of Iraqi leader Saddam Hussein's weapons programs, but added, "They never said there was an imminent threat."
Instead, he said, "They painted an objective assessment for our policy-makers of a brutal dictator who was continuing his efforts to deceive and build programmes that might constantly surprise us and threaten our interests."
Tenet said CIA analysts were "generally on target" about Iraq's missile programme, but on nuclear weapons, "We may have overestimated the progress that Saddam was making."
Political and intelligence chiefs in the US and Britain have come under growing pressure over the failure to find any chemical, biological or nuclear weapons, the presence of which was given as the chief justification for invading Iraq in March 2003.
More time needed
Tenet appealed for more time to find banned Iraqi weapons – something the US had denied the United Nations weapons inspection team before the war.
But Tenet insisted that ousted Iraqi leader Saddam Hussein had planned to resume efforts to build a nuclear bomb.
"Saddam did not have a nuclear weapon (but) he still wanted one," Tenet said.
Tenet has been embroiled in controversy over claims made about Iraq's weapons programme before. In July 2003, the CIA chief who took responsibility for President George Bush's false allegation that Iraq had tried to obtain uranium from Africa.
Tenet admitted his agency should have cut it from Bush's 2003 State of the Union address.