Lib, I hate to break it to you buddy, but the US isn't exactly popular in Iraq. Has it ever occured to you that the Iraqis might actually prefer "the terrorists" to the US? In which case, it is the United States who are the terrorists.
For God's sake, at least stop saying you're doing it on behalf of the Iraqis, and just face up to the fact that its naked agression on America's part. They want you gone man, or at least some of the more moderate ones do. The rest want you dead. Why do you think the insurgency is getting so much popular support? You can't fight the insurgents on behalf of the Iraqi people if its clear that Iraqi people are, to oversimplify it, on their side.
The 9/11 hijackers thought that the entire US population should be punished because some of them support the the US government, which has the blood of countless victims on its hands. So they crashed two planes into the WTC. And now, you're saying that the Sunnis should be punished because some of them support the insurgents, who have the blood of American soldiers (not civilians, soldiers) on their hands.
See the logic?
Not to mention the fact that the Iraqi insurgency is involved in a legitimate struggle to end an illegal occupation by a foreign power, while American agression over the years has never been defensive in nature.