No.
The United States cannot win a civil war in Iraq.
Al Qaeda is not the main problem in Iraq.
The main problem is that Iraq is really at least three countries, two with oil and one without.
Getting the south and Kurdistan to share their oil wealth with the Sunnis in central Iraq would be at least as hard as getting ExxonMobil to share their wealth with you. Not gonna happen.
At this stage, the Iraq War is simply a device for bleeding money from US taxpayers for the benefit of Halliburton, Fluor, Brown & Root, Blackwater and the weapons makers.
