Iraq is back in the political news.

Last week, al Qaeda fighters took over Fallujah, which in 2004 was the bloodiest battle for the U.S. military.

That development allowed critics to charge that those American deaths are now in vain after the U.S. withdrawal from Iraq. Said Sens. John McCain (R-AZ) and Lindsey Graham (R-SC) in statement:

When President Obama withdrew all U.S. forces from Iraq in 2011, over the objections of our military leaders and commanders on the ground, many of us predicted that the vacuum would be filled by America's enemies and would emerge as a threat to U.S. national security interests. Sadly, that reality is now clearer than ever. What's sadder still, the thousands of brave Americans who fought, shed their blood, and lost their friends to bring peace to Fallujah and Iraq are now left to wonder whether these sacrifices were in vain.”

But here's a reality check: The American public already gave up on that war.

According to a Jan. 2013 NBC/WSJ poll -- conducted close to to the 10-year anniversary of the war's start -- 59 percent of Americans said the Iraq war wasn't worth it, while 35 percent said it was.

Those numbers were virtually unchanged from the last time the NBC/WSJ poll asked the question (in 2008).