DC, here's a quote from Obama's debate comments:

"But we can't do it if we are not willing to give Iraq back its country. Now, what I've said is we should end this war responsibly. We should do it in phases. But in 16 months we should be able to reduce our combat troops, put -- provide some relief to military families and our troops and bolster our efforts in Afghanistan so that we can capture and kill bin Laden and crush al Qaeda."

The reasons for our invasion of Iraq are still hugely important because they reflect judgement. There are only two candidates and one of them exercised incorrect judgement. You cannot so easily eschew an appraisal of that judgement especially since McCain is more militant than Obama and too easily seeks recourse to warfare as a remedy.