I'll support your right to be wrong if you allow me to point out that you are wrong....
It could easily be argued that many who are killing the innocent were and are supporters of Saddam, others are people he let out of jail ....but then I guess that is the fault of the US government.....
It could easily be argued, but it doesn't square with anything our military knows about the conflict. The Ba'athists are one small group that has, at least officially, stopped fighting (well yeah, okay, I don't believe it either). The non-Ba'athist nationalists and Sunni and Shiite Islamists, along with the al Qaeda foreigners, make up the bulk of the insurgency.