1. The alleged shooter believed in the anti-Semitic conspiracy theory that "the Jews" are working to destroy white America by bringing in immigrants. It's a cousin of the idea that George Soros is paying for "the Caravan." Let's talk about anti-Semitic ideology.
2. Good summary of alleged shooter's worldview. He belonged to the far right faction that sees Trump as "controlled opposition" (or a false flag president, if you will) -- i.e. Trump claims to stand for white America but actually works for "the Jews"
3. The idea that George Soros (symbol for many on right of Jewish conspiracy) is behind Caravan isn't confined to Nazis. Here's Congressman Matt Gaetz
4. Here is popular Trumpist cartoonist Ben Garrison -- again, someone with an audience outside the Nazi right but circulating idea that Soros is working to destroy America. 
5. House GOP Leader Kevin McCarthy
6. @attackerman and @chick_in_kiev have both written about how all these Soros theories replicate classic anti-Semitic tropes. thedailybeast.com/theres-been-a-… washingtonpost.com/outlook/2018/1…
7. The Soros stuff is just one of many manifestations of the the grand anti-Semitic trope (cosmopolitan Jews are destroying traditional nations) that pervades the alt-right and shades into the respectable right. Others examples: Frankfurt School, "Globalism"
8. Anti-semitism has ancient & medieval roots but the variety we're talking about (idea that cosmopolitan Jews are destroying traditional nations) is really a hallmark of the nationalist right since the 19th century.
9. The nationalist right posits and idealizes a cohesive volk community and therefore for structural reasons needs to have an internal scapegoat upon whom internal divisions can be blamed. So in West it's naturally drawn to already existing anti-Semitic narratives.
10. Right-wing nationalism needs anti-Semitism (or some very similar ideology) for structural reasons: all nations have internal divisions & therefore there has to be someone upon whom these can be blamed.
11. Further, because capitalism is prone is recurring crisis, right-wing nationalists need someone to blame economic problems on. As nationalists, they are loath to blame wealthy who belong to ethnic majority (are part of "the people"). Hence, repeatedly, blame wealthy Jews.
12. As August Bebel famously said, "anti-semitism is the socialism of fools" -- i.e. a way of blaming structural problems of capitalism on unpopular minority. That's a big part of story, but there's more: anti-Semitism needed to explain mass uprisings.
13. Since the French Revolution, we've repeatedly witnesses popular uprisings of subaltern classes: workers, colonized, women, racial minorities, LGBT etc. This poses a conceptual problem for right-wing nationalists, who posit organic cohesion as norm.
14. For the right-wing nationalist, popular uprisings (unless of nationalist intent) are unnatural. But how to explain the discontent of workers, colonized, women, etc? Acknowledging legitimate grievances would mean having to accept social change.
15. Unable (because of commitment to social status quo) to acknowledge grievances of subaltern classes, the right-wing nationalist needs a scapegoat who can be blamed for discord. For historical reasons, easiest handy one is myth of conniving conspiratorial Jew.
16. The Soros of right-wing mythology (globalist intent on destroy cohesive nations) fit the long history of blaming internal discord on outside agitators as well as the Dolchstoßlegende. The nationalist needs a cosmopolitan nemesis.
