How did it happen here? The horror in Squirrel Hill seems doubly unthinkable, in a state not noted for extremism, and even more in a city that has long boasted its wide-ranging multiethnic cooperation. Yet of course, Pennsylvania has a deeper history of hatred and racial violence, and of startling continuities that do indeed provide a context for the slaughter at the Tree of Life.The story goes back to the turn of the last century, when Pennsylvania was at the heart of American industrialization, and of mass immigration. New ethnic and religious groups poured into the state, both into the thriving city of Philadelphia, and the industrial areas around Pittsburgh and the anthracite country. This transformation drove a reaction that focused on religious rivalries, above all on the Catholic loyalties of so many of the immigrants. Infuriated older white Protestant communities became increasingly militant. They found their voice in the Ku Klux Klan movement and made Pennsylvania a national center of Klan militancy.The numbers are astonishing. At its brief height in the mid-1920s, the Klan had perhaps 250,000 members in Pennsylvania, perhaps a quarter of whom lived in the counties surrounding Pittsburgh. We have detailed records of that membership, and we see how the Klan organized the white Protestant population of whole communities and industries. The city in the nation with the highest proportion of Klan members was Altoona. Actually, these were not Klansmen but “Klanspersons,” the movement taking a pioneering line in gender-neutral terminology. That may sound like a whimsical trivia note, but it actually highlights the movement’s broad appeal to Protestant women, and its use of ideologies of sexual purity and white womanhood.Modern readers might be amazed to see the Klan so firmly rooted so far from its Southern roots, but at this point, the sect had firmly moved its heart to the North and the Midwest, where its chief—but not exclusive—raison d’être was anti-Catholicism. That in fact goes far to explain the Klan’s sharp decline after 1924, when a draconian Immigration Act satisfied the Klan’s core demand for a steep reduction in Catholic migrants. The 1928 presidential candidacy of Catholic Al Smith sparked a brief revival.But the Klan had other grievances, which were conveniently summarized by the popular tag explaining the group’s name in terms of its bogeymen—“Kike, Koon, and Kath’lic.” The Klan’s anti-Semitism, which was always important to its ideology and propaganda, become central in the 1930s, largely in response to the New Deal and Franklin Roosevelt—or in the propagandist language of the time, of President Rosenfeld and his Jew Deal.Hitler and the European dictators aroused admiration and emulation in Pennsylvania, as the state acquired its share of rising “shirt” movements modeled on the Italian Black Shirts and German Brown Shirts. Philadelphia in particular was a flourishing center for the German-American Bund, for Italian-American Black Shirts, and for semicriminal profit-making sects like the Khaki Shirts.As the decade went on, growing persecutions of Jews in Germany raised fears of a new mass immigration of asylum seekers—of “refu-jews.” The booming far right also included a sizable Klan revival, as Klan and German Bund members undertook joint paramilitary exercises. Together, the various sects could likely count their support in the hundreds of thousands.***By 1940, Philadelphia and Pittsburgh were pullulating centers for the Christian Front, the openly pro-Nazi followers of Father Coughlin. Irish and German street gangs disrupted leftist meetings, and struck at Jewish properties and individuals. The left struck back as best they could, through street fights, and on several occasions in Philadelphia, by bomb attacks against Fascist and Nazi properties.Particularly influential in the long term was a now largely forgotten sect called the Silver Shirts, founded by William Dudley Pelley in 1933 as an explicit copy of Nazism. Stridently anti-Jewish, the movement also owed its appeal to its immersion in occult and spiritualistic theories. Pelley’s deputy Roy Zachary earned notoriety for an explicit threat to assassinate FDR.Although mainly based in the Western United States, the Silver Shirts also had a strong foothold in Pittsburgh, where Zachary and other emissaries propagandized among the anti-Roosevelt industrial elites. They made a special local appeal to Pennsylvanians through the so called “Pinckney prophecy,” allegedly an extract from the diary of U.S. founding father Charles Pinckney. This reported a lost speech attributed to Benjamin Franklin during the Constitutional Convention, arguing that “Jews are a menace to this country if permitted entrance, and ought to be excluded.” First published by Pelley in 1934, the Prophecy is a ludicrous forgery, but it became a familiar mainstay of propaganda for over a decade, and was quoted in Nazi papers in Germany.By the late 1930s, the Silver Shirts were gaining alarming strength on the Pennsylvania right, leading leftist and Jewish groups in the Pittsburgh region to campaign forcefully against the “Nazified Silver Shirt Legion.” They broke up meetings, and on one occasion forced Roy Zachary himself to flee a meeting hall through a rear exit.The new centrality of anti-Semitism in the state’s politics is symbolized by a crucial and influential organizer named Paul Winter. Winter began his career as a highly successful recruiter for the Philadelphia area Klan, and in 1928 he published a celebrated anti-Catholic and anti-immigrant tract called What Price Tolerance? But he soon ran into trouble for embezzling Klan funds, and also for his dictatorial tendencies. He formed a personal elite bodyguard and enforcement squad known as the Super-Secret Society, the “S. S. S.” The “Night Riders” of this “Black-Robed Gang” beat and intimidated opponents who questioned Winter’s shady financial dealings. He was in effect thrown out of the city, persuading him to take refuge in the northeastern community of Shavertown. By the late 1930s, Shavertown was a national center for anti-Semitic organization and propaganda.Already in his Philadelphia years, Winter had defined his racial ideology as “Nordic,” but the New Deal years made him overtly and fanatically anti-Semitic, and pro-Nazi. He was described in 1940 as “a distributor of Nazi pamphlets direct from Berlin,” and was in contact with German intelligence.One of Winter’s closest allies was Edwin Flaig, who was based at Millvale near Pittsburgh. With whatever degree of truth, Flaig claimed personal acquaintance with Hermann Göring, Wilhelm Frick, and other Nazi leaders. Flaig had attended Hitler rallies in Germany, and looked forward to the day when Hitler would use mustard gas against New York City.Flaig reputedly was involved in gun-running, and boasted of the existence of armed Nazi groups in the Pittsburgh area, disguised as rifle or sporting clubs. After all, he claimed, “Jew-hunting is going to be pretty good soon, and we are practicing.” “The boys” would “dynamite Detroit, Pittsburgh, Chicago—paralyze transportation and isolate whole sections of the country. … A blood bath is the only way out.” For what it is worth, the FBI in 1940 undertook mass arrests of pro-Nazi plotters in New York and other cities, who were allegedly plotting just such mass terrorism.Another Winter friend and visitor was James B. True, who denounced “the Jew Communism which the New Deal is trying to force on America.” He attempted to patent a type of billy club under the title of Kike Killers, and wished “to return the United States from a Talmudic dictatorship to its original republican form of government.” Winter and True were both close to Robert B. Edmondson, who published the American Vigilante Bulletin as a counterblast to the “Jew Deal.” In 1939, he relocated from New York City to become a neighbor of Winter’s in Luzerne County. Edmondson deserves our special attention for his role in laying a foundation for modern day extremism: He is a vital conduit in this grim tradition.***The racial struggles of the 1960s again stirred ultra-right militancy and armed extremism, and once again, the Klan was at the fore. And as in the 1930s, Klan racism segued naturally from simple racism into anti-Semitism of an even more consistently Nazi and genocidal tint than in the earlier era. Two main currents stand out in the process. Although the Silver Shirts evaporated as a movement in the war years, individual members persisted, and helped found influential anti-government sects like the Posse Comitatus. By the 1960s, these movements were adopting strict Christian-identity views, the idea that the authentic descendants of the biblical Hebrews are to be found only among Nordic and Germanic races: The so-called Jews are thus impostors and satanic deceivers.As the Klan revived in these years, many of its leaders followed Christian-identity teachings to the point of discarding older anti-Catholic bigotry, and in some cases actually inviting Catholic members. Those older grievances were as nothing besides the ultimate danger posed by the Jews, and by their African-American dupes and puppets.Pennsylvania especially proved fertile ground for this reorganized Klan tradition, and especially its most violent and fanatical tendency, the White Knights of the KKK. In the 1990s, the Western Pennsylvania White Knights were training followers in the use of pipe bombs, and reportedly organizing a significant terror campaign that was only aborted by federal action.The modern story of the terrorist far right must focus on one individual, who rooted himself in the world I have described, of the circle around Paul Winter. This was William L. Pierce (1933-2002), who repeatedly cited Robert Edmondson as his principal inspiration. Pierce is best known for the novel The Turner Diaries, written in 1975-76 and published in book form in 1978. The Turner Diaries is a detailed and specific account of a Nazi revolution in a near-future United States, to overthrow the Zionist Occupation Government, the ZOG, and ultimately, to exterminate the Jewish people. It is also, almost literally, a book with blood on its pages, as it has directly inspired so many real-world imitators.In the mid-1980s, a group named The Order tried to implement The Turner Diaries script, with a hair-raising plan for systematic assassinations and terror attacks. The Oklahoma City bombing of 1995 very closely followed a script laid down in The Turner Diaries, in a passage imagining the destruction of FBI Headquarters in Washington, D.C. Incidentally, the fictional Nazi movement in the book undertakes this attack after they have recovered their secret arms depot cached near the Central Pennsylvania town of Bellefonte.Pierce had his Pennsylvania readers and disciples both among organized groups and individuals. In 2009, Pittsburgh suffered a traumatic incident when Richard Poplawski murdered three police officers, a crime for which he is awaiting execution. Poplawski’s own expressed views, and those of his intimate circle, show that he was expecting a re-enactment of The Turner Diaries scenario, in which the ZOG would seize private firearms as the immediate precursor to an outright Zionist coup. (In the book, these seizures are the “Cohen Raids.”)***The Diaries originally imagined a terror campaign in the classic urban guerrilla format, of a close-knit clandestine organization, but subsequent events have shown this kind of structure to be painfully vulnerable to infiltration and disruption. Witness the collapse of The Order’s campaign in the 1980s, which left the paramilitary far right in ruins. Responding to existential crisis, extremist theorists evolved a shrewd if desperate strategy of “leaderless resistance,” which has its parallel in the “lone wolf theories of jihad” evolved by some radical Islamist splinter groups in the wake of the decimation of al-Qaida.The insight behind these theories is a simple one: If even the tightest of cell systems could be penetrated by federal agents, why have a hierarchical structure at all? Why not simply move to a non-structure, in which individual groups circulate propaganda, manuals, and broad suggestions for activities, which can be taken up or adapted according to need by particular groups or even individuals? The strategy is almost perfect in that attacks can neither be predicted nor prevented, and that there are no ringleaders who can be prosecuted. The internet offered the perfect means to disseminate information.And that brings us back to William Pierce, who followed Turner Diaries with another book that provides a prophetic description of leaderless resistance in action, which likely provides the context for the Squirrel Hill atrocity. Hunter, published in 1989, portrays a lone terrorist named Oscar Yeager (German, Jäger, meaning Hunter) who assassinates mixed-race couples. The book is dedicated to Joseph Paul Franklin, “the Lone Hunter, who saw his duty as a white man, and did what a responsible son of his race must do.” Franklin, for the uninitiated, was a racist assassin who launched a private three-year war in the late 1970s, in which he murdered interracial couples (including a couple in Johnstown, Pennsylvania.), and bombed synagogues. The fictional Yeager likewise launches armed attacks against the liberal media, against Jews, and against groups attempting to foster good relations among different races and creeds.Central to the book is the notion of revolutionary contagion. Although the hero (for hero he is meant to be) cannot by himself bring down the government or the society that he detests, his “commando raids” serve as a detonator, to inspire other individuals or small groups by his example. He aimed at the creation of a never-ending cycle of “lone hunters,” berserkers prepared to sacrifice their lives in order to destroy a society they believe to be wholly evil.Hunter has had a vast influence, and in surprising circles. It probably inspired the Islamist propagandist Anwar al-Awlaki, who carried the individualistic “lone hunter” tactic to the followers of Islamic State. And of course, the book features prominently on the websites and resources of the contemporary American far right, for whom it has proved a much more relevant and valuable weapon than the outmoded Turner Diaries. I am not privy to the investigation of Pittsburgh attacker Robert Bowers, but I would be astonished if he had not encountered Hunter, or had it in his possession—possibly through an easily accessible online download. What happened at Tree of Life was the textbook Hunter scenario.Whether we look at this long history, or if we just consider those very recent developments, we must be less startled that such an unspeakable horror could have happened in Pennsylvania, and in Pittsburgh. Those poisoned roots have always been there, visible to anyone who cares to look.***To read more Tablet coverage of the Pittsburgh massacre, click here.