Where are you getting your data?
It isn't the cannon fodder that counts. You might as well say that Hamas and Arafat were irrelevant to terrorism in the Middle East, since it was the poverty-stricken brainwashed Palestinian camp-dwellers actually wearing the bomb vests.
Attempting to distort reality to the point where the insurgency is painted as some form of popular uprising across all of Iraq is something you expect from Michael Moore, who is considerably less intelligent than you are. You might make a case that some of the Sunnis have cast their lot in that direction, but that's about it.
BTW, Iraqis are turning in insurgents and weapons caches in huge numbers. Almost every capture incident I have seen involves cooperation of Iraqis and local tribes.