I'm reading
Life and Death in the Third Reich, by Peter Fritszche, and finding it excellent. His material is letters, diaries, and other personal accounts of a wide range of Germans throughout the '30s and '40s, and his topic is the ways in which they made places for themselves in the Nazi regime, not just socially but internally: how they thought and felt, what they taught themselves and each other to do, how they reconciled some contradictions and lived with others, and so on.
The degree of similarity with Republican America is hard to overstate. Fritzsche on the effort to suppress empathy-to get Germans to make themselves no longer sympathize or care about designated victim classes, and to feel an interest in the well-being only of those approved for prospering-is particularly good, and particularly relevant. Ditto his look at how different Germans worked with the concept of constant impending doom, and its use as justification for aggression. The American soulmates of the Nazis have never been as intense or thorough about it as the originals, but the advantages of sustained effort do accumulate. The Nazis only had 12 years; the Republicans have had 30 years of really solid media hegemony, and decades of counter-New Deal effort running up to that.
But there's a particular thing the Nazis were good at that the Republicans are really terrible about: community life. The Republican machine's attachment to a particularly brutal kind of corporate capitalism makes them inclined to favor masses who are isolated and scared, and they lose out on the advantages of masses who feel strong ties to each other as well as to their shared abstractions. The Republicans' dupes are about as good as the Nazi public was when it comes to hating the Other and feeling their very way of life in imminent peril, but they are completely out of the habit of working together on their own common good, and this keeps them from the complete social transformation the Nazis set out for.
In short, we're not Nazi because we're more MBA.