United States Deputy Defence Secretary Paul Wolfowitz has said the use of "murky intelligence" is justified in the war on terror, if it prevents future attacks.
Wolfowitz says containment of Iraq did not work
He was interviewed by several US television networks following a congressional report which concluded the 11 September attacks could have been prevented if security services had shared and acted upon information.
"The lesson of 9-11 is that, if you're not prepared to act on the basis of murky intelligence, then you're going to have to act after the fact," he told the Fox News' Sunday programme.
There has been mounting criticism of the US and Britain's reasons for invading Iraq, which included charges that Saddam Hussein had chemical and biological weapons and was collaborating with Osama Bin Laden's al-Qaeda group.
No such weapons have been found and there is little evidence that the toppled Iraqi leader was in contact with al-Qaeda.
"If in 2001, or in 2000 or in 1999 we had gone to war in Afghanistan to deal with Osama Bin Laden and we had tried to say, 'it's because he's planning to kill 3,000 people in New York,' people would have said, 'well you don't have any proof of that'," Mr Wolfowitz told NBC television network.
The congressional report was saying "we should have connected these murky dots ahead of time," he told CBS's "Face the Nation" programme.
"Well, you can't have it both ways. If you wait until you have
absolute certainty about terrorism, you are really saying, we'll
wait until after the fact and deal with it.
"The lesson of 9-11 is that approach doesn't work anymore. We
cannot deal with terrorism after the fact."
Iraq policies 'failed'
He said the policy of containment of Iraq, in place since
the end of the first Gulf War, had failed.
Blair and Bush said Iraq had weapons of mass destruction
The Americans killed in attacks on the USS Cole off the Yemeni port of Aden in October 2000 and on the Khobar Towers barracks in Saudi Arabia in 1996 were in the Middle East to contain Saddam Hussein, he noted.
"Twelve years of containment was a terrible price for us, and
for the Iraqi people it was an unbelievable price," he told NBC.
"We went to war, and I believe we are still fighting terrorists
and terrorist supporters in Iraq, in a battle that will make this
country safer in the future from terrorism."
But leading Democratic senator, Carl Levin, has questioned whether intelligence on
Iraq really was presented as being unclear.
"It sure didn't sound murky before the war. There were clear
connections, we were told, between al-Qaeda and Iraq. There was no
murkiness, no nuance, no uncertainty about it at all. It was very
clear, very certain. That's the way it was presented to the American
people," he told CBS.