Even if it was, Saddam couldn't control his own country.
Whoa, there. You're making a serious error of logic on a couple different levels. For one thing, he "couldn't control [that sector of] his own country" because we were keeping him out of that sector. Secondly, if this al-Ansar character was operating in Kurdish-controlled territory, wouldn't that implicate the Kurds in some way?
Who was the leader of Iraq? Saddam.... If he couldnt control his own territory, plus you have other intel of his security forces meeting with terrorists. At some point the Bush doctrine comes into play.