Would you be able to link to a source about the UN weapons inspectors or something similar? All I have is pretty much hearsay and I was young enough when the towers fell that I understood "bad guys did it" but not much more.
Some links: https://www.npr.org/2013/03/19/174708587/u-n-weapons-inspect... https://www.cnn.com/2013/10/30/world/meast/iraq-weapons-insp...
Here is something about the Iraq-Al Qaeda link they tried to proof.
https://en.wikipedia.org/wiki/Saddam_Hussein_and_al-Qaeda_li...
I don't know if Bush and friends really believed their claims but if you looked at it from a neutral point of view it was very clear that they had made up their minds to invade Iraq and desperately tried and failed to find evidence.