In 1952, the American scholar Carl Mayer, a Jewish man with German heritage, spent a year living and teaching in West Germany. He explains why in his Foreward (page xvii):

I wanted to see this monstrous man, the Nazi. I wanted to talk to him and to listen to him. I wanted to try to understand him. We were both men, he and I. In rejecting the Nazi doctrine of racial superiority, I had to concede that what he had been I might be; what led him along the course he took might lead me.

The book is devastating in the way that it speaks to us, today, in the United States.

Page 166:

“What no one seemed to notice,” said a colleague of mine, a philologist, “was the ever widening gap, after 1933, between the government and the people. Just think how very wide this gap was to begin with, here in Germany. And it became always wider. You know, it doesn’t make people close to their government to be told that this is a people’s government, a true democracy, or to be enrolled in civilian defense, or even to vote. All this has little, really nothing, to do with knowing one is governing.

“What happened here was the gradual habituation of the people, little by little, to being governed by surprise; to receiving decisions deliberated in secret; to believing that the situation was so complicated that the government had to act on information which the people could not understand, or so dangerous that, even if the people could understand it, it could not be released because of national security. And their sense of identification with Hitler, their trust in him, made it easier to widen this gap and reassured those who would otherwise have worried about it.

“This separation of government from people, this widening of the gap, took place so gradually and so insensibly, each step disguised (perhaps not even intentionally) as a temporary emergency measure or associated with true patriotic allegiance or with real social purposes. And all the crises and reforms (real reforms, too) so occupied the people that they did not see the slow motion underneath, of the whole process of government growing remoter and remoter.

Pages 168-170, continuing directly:

To live in this process is absolutely not to be able to notice it—please try to believe me—unless one has a much greater degree of political awareness, acuity, than most of us had ever had occasion to develop. Each step was so small, so inconsequential, so well explained or, on occasion, ‘regretted,’ that, unless one were detached from the whole process from the beginning, unless one understood what the whole thing was in principle, what all these ‘little measures’ that no ‘patriotic German’ could resent must some day lead to, one no more saw it developing from day to day than a farmer in his field sees the corn growing. One day it is over his head.

“How is this to be avoided, among ordinary men, even highly educated ordinary men? Frankly, I do not know. I do not see, even now. Many, many times since it all happened I have pondered that pair of great maxims, Principiis obsta and Finem respice—’Resist the beginnings’ and ‘Consider the end.’ But one must forsee the end in order to resist, or even see, the beginnings. One must forsee the end clearly and certainly and how is this to be done, by ordinary men or even by extraordinary men? Things might have changed here before they went as far as they did; they didn’t, but they might have. And everyone counts on that might.

“Your ‘little men,’ your Nazi friends, were not against National Socialism in principle. Men like me, who were, are the great offenders, not because we knew better (that would be too much to say), but because we sensed better. Pastor Niemöller spoke for the thousands and thousands of men like men when he spoke (too modestly of himself) and said that, when the Nazis attacked the Communists, he was a little uneasy, but, after all, he was not a Communist, and so he did nothing; and then they attacked the Socialists, and he was a little uneasier, but, still, he was not a Socialist, and he did nothing; and then the schools, the press, the Jews, and so on, and he was always uneasier, but still he did nothing. And then they attacked the Church, and he was a Churchman, and he did something—but then it was too late.”

“Yes,” I said.

“You see,” my colleague went on, “one doesn’t see exactly where or how to move. Believe me, this is true. Each act, each occasion, is worse than the last, but only a little worse. You wait for the next and the next. You wait for one great shocking occasion, thinking that others, when such a shock comes, will join with you in resisting somehow. You don’t want to act, or even talk, alone; you don’t want to ‘go out of your way to make trouble.’ Why not?—Well, you are not in the habit of doing it. And it is not just fear, fear of standing alone, that restrains you; it is also genuine uncertainty.

“Uncertainty is a very important factor, and, instead of decreasing as time goes on, it grows. Outside, in the streets, in the general community, ‘everyone’ is happy. One hears no protest, and certainly sees none. You know, in France or Italy there would be slogans against the government painted on walls and fences; in Germany, outside the great cities, perhaps, there is not even this. In the university community, in your own community, you speak privately to your colleagues, some of whom certainly feel as you do; but what do they say? They say, ‘It’s not so bad’ or ‘You’re seeing things’ or ‘You’re an alarmist.’

“And you are an alarmist. You are saying that this must lead to this, and you can’t prove it. These are the beginnings, yes; but how do you know for sure when you don’t know the end, and how do you know, or even surmise, the end? On the one hand, your enemies, the law, the regime, the Party, intimidate you. On the other, your colleagues pooh-pooh you as pessimistic or even neurotic. You are left with your close friends, who are, naturally, people who have always thought as you have.

Page 171, continuing:

“And one day, too late, your principles, if you were ever sensible of them, all rush in upon you. The burden of self-deception has grown too heavy, and some minor incident, in my case my little boy, hardly more than a baby, saying ‘Jew swine,’ collapses it all at once, and you see that everything, everything has changed and changed completely under your nose. The world you live in—your nation, your peoplemdash;is not the world you were born in at all. The forms are all there, all untouched, all reassuring, the houses, the shops, the jobs, the mealtimes, the visits, the concerts, the cinema, the holidays. But the spirit, which you never noticed because you made the lifelong mistake of identifying it with the forms, is changed. Now you live in a world of hate and fear, and the people who hate and fear do not even know it themselves; when everyone is transformed, no one is transformed. Now you live in a system which rules without responsibility even to God. The system itself could not have intended this at the beginning, but in order to sustain itself it was compelled to go all the way.

Page 173, continuing:

“Once the war began,” my colleague continued, “resistance, protest, criticism, complaint, all carried with them a multiplied likelihood of the greatest punishment. Mere lack of enthusiasm, or failure to show it in public, was ‘defeatism.’ You assumed that there were lists of those who would be ‘dealt with’ later, after the victory. Goebbels was very clever here, too. He continually promised a ‘victory orgy’ to ‘take care of’ those who thought that their ‘treasonable attitude’ had escaped notice. And he meant it; that was not just propaganda. And that was enough to put an end to all uncertainty.

“Once the war began, the government could do anything ‘necessary’ to win it; so it was with the ‘final solution of the Jewish problem,’ which the Nazis always talked about but never dared undertake, not even the Nazis, until war and its ‘necessities’ gave them the knowledge that they could get away with it. The people abroad who thought that war against Hitler would help the Jews were wrong. And the people in Germany who, once the war had begun, still thought of complaining, protesting, resisting, were betting on Germany’s losing the war. It was a long bet. Not many made it.”

—Milton Mayer, They Thought They Were Free: The Germans, 1933-1945. First published by the University of Chicago Press in 1955; these excerpts are from the 1969 edition.