The media has undergone a strange change of mindset. Immediately before last Tuesday’s election, many reporters and commentators ignored or dismissed the consensus among forecasters and betting markets that President Obama was very likely to defeat Mitt Romney and acted instead as if the candidates were neck and neck or Romney was ahead. Afterward, however, coverage of how Obama won betrayed far less uncertainty about the outcome of the election, which was frequently portrayed as a fait accompli—an inevitable consequence of how Romney’s image was defined by Obama’s early ads or overwhelmed by the President’s superior ground game.

Before the election, for instance, Wall Street Journal editorial page editor Paul Gigot said on the October 27th edition of Journal Editorial Report that “Polls continue to show the race in a dead heat nationally, and too close to call in no fewer than 10 swing states.” Afterward, however, Gigot asserted on ABC’s This Week that while Romney “could have won,” he “never recovered” from the negative ads Obama’s campaign ran against him during the summer. “[I]f he wanted to win, clearly they needed to respond somehow, and they didn’t.”

Similarly, National Journal’s Michael Hirsh declared after the election that “perhaps the most successful chunk of advertising money ever spent in modern American political history was the initial $50 million or so the Obama team devoted last spring to defining Romney as an exploitative, job-exporting Wall Street plutocrat.” While his lede states that “Romney could have won,” he approvingly quotes GOP strategist Rick Tyler saying “The early ads paid off… I don’t think [Romney] ever really recovered.” But just a few weeks ago, Hirsh described Obama as “an imperiled incumbent who faces a must-win situation” in his second debate with Romney and later described Hurricane Sandy as necessary to stop Romney’s (mythical) “momentum.”

ABC/Washington Post pundit George Will went even further than Gigot or Hirsh before the election in predicting a Romney win with 321 Electoral College votes. When that prediction was falsified, Will reversed course and declared that the outcome was “foreshadowed by Mitt Romney struggling as long as he did to surmount a notably weak field of Republican rivals.” The foreshadowing was apparently more obvious in retrospect than it had been five days earlier when he made his prediction.

This pattern of seeing an outcome as inevitable in retrospect, which is known as “hindsight bias,” was unfortunately all too predictable (and not just in hindsight!)—here’s what the New York Times’s Benedict Carey wrote before the election:

Amid the many uncertainties of next Tuesday’s presidential election lies one sure thing: Many people will feel in their gut that they knew the result all along. Not only felt it coming, but swear they predicted it beforehand—remember?—and probably more than once.

These analysts won’t be hard to find. They will most likely include (in addition to news media pundits) neighbors, friends, co-workers and relatives, as well as the person whose reflection appears in the glare of the laptop screen. Most will also have a ready-made argument for why it was inevitable that Mitt Romney, or Barack Obama, won—displaying the sort of false, after-the-fact “foresight” that psychologists call hindsight bias.

The hindsight bias we have seen is fueled in part by the wave of post-election spin that follows every election. Inevitably, the press reports, as it has this time around, that the winner won due to the strategic genius of the candidate and his campaign (often based on source-greasing interviews with staffers taking a victory lap) and the loser lost due to disarray and mistakes within his campaign (typically fueled by internal leaks seeking to deflect blame).

Brendan Nyhan is an assistant professor of government at Dartmouth College. He blogs at brendan-nyhan.com and tweets @BrendanNyhan.