For the 50th anniversary of Pearl Harbor, we devoted the entire December issue to the Second World War. On December 3, a historian at a Midwestern college wrote my boss to say we’d done a pretty shabby job: The articles were “weak on factual accuracy, which, of course, makes them suspect in interpretation.”

He was particularly censorious about a piece by the naval historian Edward Beach that examined how America recovered from calamity to organize and win the war in the immensities of the Pacific—a campaign which Beach had observed  through the periscope of his submarine. I passed the letter along to Captain Beach, who replied far more graciously than I would have had I been upbraided for not comprehending events in which I had actually taken part. He defended his position ably and persuasively, but what brings this exchange to mind just now is that sentence about how errors of fact make an article suspect in interpretation.

This is true, of course—you can’t draw proper inferences from faulty data—but it is true only to a degree. In Captain Beach’s case, his only real error, which put Japanese casualties on Guadalcanal higher than they were, diminished neither his grasp of the Pacific war, nor the value of his article.

Yet it is surprising how often we get letters that say, in effect: Because you were wrong about the (and here any detail can be inserted—the model of this locomotive, the color of that flower, the age of those twins), I can no longer trust anything you print.

I don’t believe that. But this is not to say that such details don’t matter, and in fact, we try our best to get them right. All our copy is proofed and checked several times during its journey toward print, but the main fact-checking burden is shouldered by Nathan Ward, who is the inheritor of a system that goes back to the beginnings of the magazine. It mandates that each word in each article be checked against the author’s source and, should any conflict arise, against other sources. We have a fine small library of American history and many knowledgeable consultants who are generous with their advice, but, sooner or later, the trail leads to the limitless resources of the main reference branch of the New York Public Library, and, often, at the end of the day, I see Nathan coming in with the mildly concussed look that makes me think of Jack’s exclamation upon going through the “Army lists of the last 40 years” in The Importance of Being Earnest: “These delightful records should have been my constant study!”

At the end of the process, Nathan has produced a manuscript overwritten to near illegibility, with red slashes of confirmation. His changes have been keyed in and confirmed on the final copy, and we all wait for the issue with the hope that, this time, everything is perfectly accurate. It rarely is. Magazine publishing is a continuous