On Saturday, 18-year-old Payton Gendron parked his car in front of the entrance to a Tops Supermarket in a Black neighborhood in Buffalo, New York. Exiting the car wearing metal armor and holding an assault rifle, he shot and killed a female employee in front of the store, and a man packing groceries into the trunk of his car. After entering the store, he murdered the store’s guard, and by the end of his killing spree, he had shot 13 people, killing 10 of them.

Eleven of the people he shot were Black, and two were white. As the manifesto he left behind makes clear, this was fully intentional. The first listed goal in his manifesto was to “kill as many blacks as possible”.

Gendron was a meticulous planner. He live-streamed his massacre, and the video begins with him following to the letter the beginning of the plan he lays out in the manifesto..

But the manifesto – which is meant to inspire and instruct subsequent attacks – also outlines the ideology that inspired the murders. Gendron was motivated by a classic version of White Replacement Theory, the view that a cabal of global elites is trying to destroy white nations, via the systematic replacement of white populations. According to White Replacement Theory, the strategies employed by these “global elites” include the mass immigration of supposedly “high fertility” non-whites, and encouraging intermingling between members of non-white races and whites. Gendron was deeply influenced by a series of recent mass killers who were animated by white replacement theoryincluding Brenton Tarrant, whom Gendron openly acknowledges as his model. In Christchurch, New Zealand, Tarrant massacred 51 people at a Mosque in the name of White Replacement Theory, also live-streaming his actions.

Gendron’s manifesto begins in a similar fashion to Tarrant’s, by decrying the “white genocide” that will result from the supposedly low fertility rates of white populations and the high fertility rates of non-white immigrants brought in to “replace” them. It is more openly anti-Black than Tarrant’s manifesto – it is a deeply American version, with roots in Jim Crow and lynching. It is also vastly more explicitly antisemitic.

Ten pages of Gendron’s manifesto are devoted to arguing for a genetic basis for the racial IQ gap, as well as (ironically) a genetic basis for higher rates of violent crime. It’s clear that Gendron closely follows various academic debates about race, IQ, and crime.

According to the ideology guiding Gendron, Black people are not intelligent enough to engineer the replacement of whites, and the destruction of their civilization. The real actors behind White Replacement, according to Gendron, are the Jews, a topic which occupies the subsequent 29 pages of his manifesto.

Gendron’s lengthy section on Jews purports to document Jewish hatred of non-Jews. It includes a section of Talmud quotes supporting Gendron’s thesis that Jews hate Christians, and a section documenting supposed control of academia, media, and industry (focusing on the pharmaceutical industry). Gendron ties Jews to child abuse and pedophilia. The section mocks a supposed Jewish fixation on environmental causes of Black crime. Gendron argues that Jews are behind Black social and political movements and organizations, including the NAACP and Black Lives Matter.

Gendron also argues that Jews are behind the movement for transgender inclusivity, supposedly sponsoring transgender summer camps for “Scandinavian style whites”.

The section ends by blaming Jews for creating “infighting” between people and races. The example Gendron’s manifesto provides is that “Jews are spreading ideas such as Critical Race Theory and white shame/guilt to brainwash Whites into hating themselves and their people”.

The ideology that motivated Gendron’s mass murder in Buffalo, White Replacement Theory, has a lengthy and blood-soaked 20th century history. Since 2011, it has been the explicit motivation for over 160 murders, including Norway’s Anders Breivik’s slaughter of 77 people, mostly immigrants, in 2011, Dylann Roof’s mass murder of Black churchgoers in Charleston, South Carolina, in 2015, the Tree of Life Synagogue killings in 2018, and the murder of 23 people, mostly immigrants, in El Paso, Texas, in 2019.

Mass atrocities do not occur in a vacuum. They are enabled by a present normalization of a lengthy previous history, a process that the philosopher of mass killing Lynne Tirrell labels the social embeddedness condition. White Replacement Theory was the dominant structuring narrative of Nazi ideology. Adolf Hitler also announced his genocidal intent in a lengthy manifesto about the supposed Jewish threat to white civilization, entitled Mein Kampf, which was published in 1924. Hitler also was obsessed by mass immigration, and the threat it posed to “white civilization.”

Currently, White Replacement Theory has been mass popularized and normalized, perhaps chiefly by the American political commentator Tucker Carlson. It is rapidly moving to the center of the mainstream narrative of America’s Republican party. In this form, it appears stripped of its explicit connection to antisemitism. You will not find Tucker Carlson asserting that the Jews are behind the mass replacement of American whites that he bemoans regularly in what is regularly the most watched cable news show in the United States among adults 25-54.

But what Carlson has been doing is spending an entire year repeating a conspiracy by Christopher Rufo that says that American education has been infected by a pro-Black ideology (CRT) that was created by German Jewish Marxist intellectuals (the Frankfurt School). And that while the CRT version of this conspiracy theory is new, it is a direct descendent of the “cultural marxism” conspiracy theory, which was a primary topic of Breivik’s manifesto.

The fact that Carlson does not mention American Jews as a target by name should be cold comfort to American Jews. Every single right wing anti-Semite in America who watches Tucker Carlson’s show hears him as denouncing Jews when he regularly platforms the 20th century’s worst anti-Semitic conspiracy theory.

Some American Jews hope that by identifying as white, and lending their support to racist narratives about IQ and crime, they can diminish rightwing American antisemitism. This is a terrible error. American Ku Klux Klan ideology in the 1920s strongly overlapped with Nazi ideology, placing Jews at the center of a conspiracy fomenting a supposed race war to overthrow white civilization. American Jews who support Tucker Carlson and his ilk, that is, others who repeat the White Replacement narrative, are supporters both of anti-Black racism, and antisemitism in its most violent form.

It is in the tracts of the 20th century’s most explicit antisemites that we find the development of White Replacement Theory, who used it to justify the mass killing of Jews. Gendron’s manifesto reveals yet again the unbreakable historical link between anti-Black racism and antisemitism. Any supporter of White Replacement Theory is a clear enemy of the Jewish People.

America has many mass shootings. But this mass killing of Black Americans in a Buffalo supermarket must serve as a wake-up call to our country. White Replacement Theory is deeply ingrained in the worst aspects of American and European history. With its attacks on “Critical Race Theory”, this is a fact that the American political right is deliberately and knowingly trying to erase from our collective consciousness, so they can appeal to it again as a political weapon against liberal democracy.

As Gendron’s manifesto makes clear, White Replacement Theory is not just an attack on minorities. It is a weapon directed by fascists at American democracy itself.