From your link:
"At a Senate hearing, Duelfer was asked why _ if Saddam did not have weapons of mass destruction before the 2003 invasion _ he did not simply comply with U.S. and U.N. demands in an attempt to avert the war. Duelfer said Saddam's instincts were always to negotiate _ to seek something in return before giving something up.

"He had not realized the nature of the ground shift in the international community," after the Sept. 11, 2001, attacks, Duelfer said. "

This makes a lot of sense to me. Also remember that Saddam's palaces looked like they were right out of the '70s. The guy wasn't paying much attention to what was going on in the world.
Add to this that even people who are "plugged in"- but not living in the US- did not fully understand the affect of 911 on American politics.