Wasserstein has a point. In my article Fuhrer-Principal, I argued something similar:

"How could she [Arendt], a critic of totalitarianism, defend Heidegger intellectually? The answer, paradoxically, is that Arendt’s critique of totalitarianism owes a great deal to Heidegger’s critique of democracy. Arendt rejected Heidegger’s political affiliation to the NSDAP, but she shared the underlying philosophy, adapting it to an altogether distinct purpose. ...

In 1945 Heidegger struggled to persuade the denazification committee that he had been an anti-nazi all along. In a document written for the hearings, ‘Facts and Thoughts’ he says that in the winter of 1939/40 he came to analyse the ‘universal rule of the will to power within history, now understood to rule the planet’. Now the ‘domination of the indifferent mass’ was seen to characterise not just Russia and America, but Germany, too: ‘Today everything stands in this historical reality, no matter whether it is called communism, or fascism, or world democracy.’

Heidegger’s apologetic argument is important, because in many respects Hannah Arendt shares it. She too sees Fascism as the product of mob rule. In her classic work On Totalitarianism, she argues that ‘a mixture of gullibility and cynicism ... became an everyday phenomenon of masses’ and the basis of totalitarian power. (On Totalitarianism, p382) "

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