"Historically, working class was far more likely to fall for nationalism than for socialism, let alone internationalism"
Really? From what I've read, the National Socialist Party's membership and voters were heavily skewed towards students, petit bourgeois types, and peasants, whereas most industrial workers voted Socialist (and not a few for the KPD). There was a problem of national chauvinism in the socialist movement (which is what Lenin addressed), but as he argued, that was largely a preoccupation of the parliamentary and official union representatives. The out-and-out nationalists were the students and intellectuals, shopkeepers, small farmers, broken down aristocrats.
If you were looking for the sociological equivalent of the Nazi Party today, you would find it in Greenpeace, or Plane Stupid,