They knew

Murray Waas for National Journal:

Ten days after the September 11, 2001, terrorist attacks on the World Trade Center and the Pentagon, President Bush was told in a highly classified briefing that the U.S. intelligence community had no evidence linking the Iraqi regime of Saddam Hussein to the attacks and that there was scant credible evidence that Iraq had any significant collaborative ties with Al Qaeda, according to government records and current and former officials with firsthand knowledge of the matter.

Fast forward one year, just before the congressional vote on authorizing the war, Waas notes:

"You can't distinguish between Al Qaeda and Saddam when you talk about the war on terror," President Bush said on September 25, 2002.
The next day, Rumsfeld said, "We have what we consider to be credible evidence that Al Qaeda leaders have sought contacts with Iraq who could help them acquire … weapons-of-mass-destruction capabilities."

It would be dishonest, reprehensible, corrupt, even shameless to suggest they were lying.