This "Club" and its views represent the kind of "Ku Kluxery" that H. L. savaged during his entire journalistic career. In my opinion, the fact that they hijacked his name for their "Club" is an insult to H. L.'s memory. Mencken was an iconoclast of the first order. He was the neighborhood "smart ass" who poked fun at anything that represented the kind of "tin pot" values held by the vast majority of Americans. He was an autodidact who had very little regard for college professors and other "intellectual" vermin. He admired men and women of ability whether they were authors, printers or bricklayers. He was once accused of not supporting anything. His reply was the he was vastly in favor of common sense, common decency and common courtesy and that this made him forever ineligible for public office in the US. I have a feeling that this would also make him ineligible for membership in this "Club".
As to the author's characterization of Mencken as a "casual racist", the jury is still out on this matter. The cited quotes are accurate. However, Mencken's views and actions regarding Jews and African-Americans were complex and contradictory. For example, he promoted African-American writers when he was editor of The Smart Set and The American Mercury. He entertained African-Americans in his home in Baltimore at a time when Jim Crow was alive and well in the US and parts of Maryland. He provided encouragement to many of the African-American writers who were part of the Harlem Renaissance. As to Jews, most of his closest friends and associates were Jewish including Alfred Knopf, his publisher, and George Jean Nathan, his co-editor on the Smart Set and The American Mercury. Many of his friends in Baltimore were Jewish. In the 1930's when the NAZI's were persecuting the Jews, he suggested that the US open its doors as widely as possible to allow them to emigrate. Unfortunately, the anti-semites in the US and Congress did not share his views. Hardly the actions of a "casual racist". Nonetheless, quotes like those cited in this article do paint a negative picture which the casual observer could characterize as racist.