It took more than twelve years of the hard slog in the original post-9/11 theater, but according to Gallup, Americans have finally made the transition to opposition to the Afghanistan War. Or, actually, maybe not quite yet. The result of their latest survey is a virtual tie well within the margin of error, but there’s no debating the trend.

Even Gallup seems a little mystified on how to report the findings. Their headline states, “More Americans Now View Afghanistan War as a Mistake,” but note the subtle difference in the lead, emphasis mine:

For the first time since the U.S. initially became involved in Afghanistan in 2001, Americans are as likely to say U.S. military involvement there was a mistake as to say it was not.

Both are actually true.  On a percentage basis, more Americans than ever before think the war was a mistake — 49%, as opposed to 44% last year and 43% in 2010. Forty-eight percent believe it was not a mistake to send troops to Afghanistan in 2001. Given the vagaries of the margin of error, it’s both “as likely” that Americans consider it a mistake and that the numbers of those who think so have grown.

It may not yet mean that more Americans think it was a mistake than those who don’t, as National Journal assumed in the virtual split:

A plurality of Americans now believes that it was a mistake to send soldiers to fight in Afghanistan after the terrorist attacks of Sept. 11, 2001, marking the first time in the war’s history that fewer Americans supported the combat effort than opposed it.

Forty-nine percent of Americans now believe the war was not ours to fight, according to a new Gallup Poll, compared with 48 percent who still believe chasing the country’s Qaida cells was the right thing to do. The margin is slight, but it marks a steep decline in those favoring the intervention over the years, which once registered at a high of 93 percent in early 2002.

But it has taken Americans longer to turn on its longest war than any other fought since the Korean War. It took the country only six months to sour on that campaign, in part due to Chinese intervention in North Korea that helped create a quagmire.

Similarly, Americans turned against the Vietnam War relatively quickly. About a quarter of Americans told Gallup they opposed what Lyndon Johnson once dubbed “that bitch of a war” when the polling service first gauged public opinion in the early summer of 1965, while six in 10 supported it. By October 1967, 47 percent saw involvement there as a mistake, compared with 44 percent who supported it.

This is hair-splitting, though. Even if this isn’t the precise moment when the calculus flipped, it’s coming and probably sooner rather than later, as Gallup’s series shows:

When Barack Obama took office in 2009, the split was more than 2:1 in favor of the war. Obama campaigned in part by promising to end the “distraction” in Iraq, where we were fighting al-Qaeda, and increase troop strength in Afghanistan to fight the Taliban. George Bush ended up authoring the Iraq drawdown, and Obama did increase troop levels in Afghanistan — while talking about withdrawal at the same time. As I wrote at that time, his speech announcing his version of a surge sounded more like “a slow-motion Dunkirk” than a plan for victory. In fact, Obama never mentioned “victory” in a speech that ran more than 4,000 words.

That was more than four years ago. Since then, Obama has given Americans no solid justification for conducting the war in Afghanistan, preferring to discuss withdrawal timetables and focus on exit strategies. The surprise here isn’t that public opinion is turning; the surprise is that it took as long as it did.