If Iraq was a US state ? Would the attack have been similar ?

Last I checked, the majority of civilians being killed in Iraq have been killed by the same militants who are claiming to be liberating Iraq from the United States.

That would depend on whether there was oil in that state or not. Destroying the leader does not make such an impact. In my view the Americans and British were wrong to go in to Iraq, there are many other countries where they have the same type of rulers but no oil and neither the American or British governments seem to be bothered by these. Maybe it's because they would not profit from interfering.

that would be a completely different situation apples and oranges.