Twenty-one years ago, a time bomb blew up beneath the posthumous reputation of H. L. Mencken—one that he had constructed himself. With the publication of excerpts from his diary, which he had placed under time-seal prior to his death in 1956, a new generation of readers learned that the most celebrated American critic of the Roaring Twenties had harbored a wide variety of politically incorrect opinions, some of which could fairly be described as ugly. Those who were already familiar with Mencken’s work were far from surprised, for it had become apparent long before a stroke forced him into retirement in 1948 that he had complicated and equivocal feelings about Jews, just as he had never made any secret of his belief that blacks as a group were congenitally inferior to whites. But these sentiments shocked those who had admired him without reading him. Although the resulting hullabaloo got Mencken back into the newspapers after a long absence, it also made him radioactive in bien-pensant circles.

Today Mencken is an unperson in the academy, yet he continues to be both written about and read with avidity by a considerable number of his fellow countrymen. Not only are most of his books in print, but three full-length biographies (one of which is by me) have been published since The Diary of H. L. Menckencame out at the end of 1989. Now the Library of America has put its stamp of institutional approval on his oeuvre with a two-volume