The decade from 1914 to 1924 was harrowing for American Jews like Kallen. As the historian John Higham later pointed out, “virtually the whole system of anti-Semitic discriminations,” including restrictive quota systems in education, barriers in business activity and employment, and residential discrimination, “was worked out by 1917.” In addition, the national origins quotas legislation of 1921 and 1924 severely restricted Jewish immigration. Although Jews were not the only group to whom the Mother of Exiles closed the golden door, “the Jews faced a sustained agitation that singled them out from the other immigrant groups blanketed by racial nativism—an agitation that reckoned them the most dangerous force undermining the nation.” The decade also saw the lynching of the Jewish factory superintendent Leo Frank in 1915, which spurred both the establishment of the Anti-Defamation League, dedicated to fighting antisemitism and other forms of bigotry, and the revival of the Ku Klux Klan, which added antisemitism to the antiblack racism of the original Klan. By the 1920s, the new Ku Klux Klan had more than four million members, Klan members served in all levels of government, and the organization wielded political power throughout the nation.
Kallen’s postscript described the Klan as part of a broader reaction against modernizing and liberalizing changes in America, a reaction that he suggested was also apparent in the nativism, pseudo-scientific racism, and religious fundamentalism of the decade from 1914 to 1924. (The Scopes trial would take place in 1925, a year after the publication of Kallen’s book.) The Klan’s membership, Kallen wrote, is “recruited from every class and every station in the United States that considers itself ‘native, white and Protestant.’” Fueled by status fears and anxieties, the Klan directed its “animating hatred” at every outgroup that deviated from this type. He summed up its viewpoint this way: “The old values that rule the common life are in danger. Arm, arm, lest they be destroyed.”
Much as the sociologist Daniel Bell would later describe the radical right of the 1960s as fighting modernity in the shadow of Communism, Kallen described the Klan as a “convulsive effort” to prevent the dissolution of the “old ways and standards of life in the United States” by modern industry, science, and democracy. Also like Bell, Kallen suggested that the effort was ultimately doomed to failure. “There is a Quixotism in [the Klan],” he wrote, albeit “a sordid and degraded Quixotism, without grace, without kindness.”