That is a good point. Since I don't know what the original mission in Iraq really was, I can't say with any certainty how much it has crept. However, it was sold as something that could be accomplished relatively quickly and as a mission that would pay for itself through Iraqi oil sales. The reality on the ground there is quite different. If the ultimate plan is to make war on Iran, we are well situated from a tactical point of view.
The original mission in Iraq was: Seizing/Destroying their weapons of Mass Destruction and deposing Sadam Hussein.
The new mission: Bring peace to the Middle East through military force. After all nothing says lovin like a good ass-kicking. I'm not sold that peace can be obtained by a war machine though.
Also, the only real difference between Republicans and Democratics is that Republicans want to take my money and give it to the rich, while Democrats want to take it and give it to the poor. But neither of them want to give me squat.
Call me old fashioned but I believe in the values the country was founded on: Non-intervention, minimal taxes, a union of the States, and the government stays out of people's business (read: healthcare/medicare/medicaid, excessive foreign aid, war on drugs, social security, wellfare and any other hot social reform like taxing pizza so people aren't fat... wtf??), and guns
But those ideals are a thing of the past. So I don't follow politics very closely anymore.