Jeez. 41% of Americans polled still think there was a link between Saddam Hussein and the events of 9/11.
Of course, the American media, with the exception of Knight Ridder, aided and abetted in the deception by utterly failing to challenge any of the Bush Administration's false claims made during the run-up to the invasion. (Bill Moyer's Buying Into the War documentary--which you can view here--deftly highlights this horrible dereliction of duty by American media.)
The Bush Administration benefited from Americans associating Saddam or Iraq with 9/11 or al-Qaeda. (This made as much sense as associating President Fox or Mexico with 9/11 or al-Qaeda.)