Watching Trump's dark, apocalyptic speech last week, Bernie Sanders asked in a tweet if he was running for president or dictator. And at the DNC this week, speakers were unafraid to call him a dangerous demagogue.

Think that's hyperbole? Chris Christie has said that Trump's first move as President would be a clean sweep of the Civil Service, which is supposed to be above politics. As discussed here on the Huffington Post, that move would be very much like something Hitler did in Germany to put the bureaucray under his personal control.

I've been thinking about Hitler and Trump a lot lately. For a long time, I resisted the comparisons between them because they seemed too glib in a country where "Gestapo" and "Nazi" and "jackboots" are eventually thrown into almost every argument. Then I read a scary New Yorker article analyzing Trump's speeches and how they affect people. I recommend the article highly for anyone who doubts he's an inflammatory, authoritarian, radical, unstable menace to our democratic way of life.

And then find a copy of Walter Kempowski's short book Did You Ever See Hitler? which I've read in English and the original German.

A prolific German author who died in 2007, Kempowski compiled the book from over 300 interviews with people of all ages and professions. It gives you a crowd's-eye view of Hitler from the 1920s through the end of World War II, concentrating on the effect he had on people, and was still having decades later.

Some saw him only once, or barely at all in a motorcade rushing past. Others saw and heard him often in Berlin. The older respondents were the generation that "had fallen for Hitler" and tried to make sure that "the memory of this fall -- and the memory of the man -- died out."

There are plenty of Germans in the book who almost brag that they weren't impressed by Hitler, or that they found his manner or face weird ("like a pink marzipan pig"). Then there are others who said they couldn't imagine he was going to be so powerful. Some of these same people report many public appearances in the 1930s that were less than crowded, and cities where Hitler wasn't wildly popular. Though as one man notes wryly, after the war, every German city claimed it had disappointed Hitler with small crowds.

But there are many more accounts of the elaborately stage-managed productions that thousands or people swarmed to, even if the school children or Hitler Youth were required to be there. And one after another, people talk about the hysteria Hitler evoked in women and girls: "The women were howling with delight," "They were peeing in their pants with excitement, and the older women were moaning as if the Savior were coming," "The women turned their eyes up so that the whites showed, and dropped like flies. Like slaughtered calves they lay there, breathing heavily," "We hardly dared wash our hands for three days, we were so affected simply because he had touched them."

Though many interviewees told Kempowski that Hitler didn't move them, the main impression this amazing book leaves is the strange mixture of the quotidian and the bizarre. You can almost feel people waiting for hours with their feet hurting, hungry and thirsty, and then coming to life when they see Germany's new God appearing, blocking out the sun.

Trump's bluster, contempt, xenophobia, unpredictability, disregard for international law and freedom of the press, and his rage are strongly reminiscent of Hitler. So is his playing to the very worst in his audience--like when he encourages violence or mocks the disabled. The savage roar of the crowds, the hysteria, and the vicious anti-Clinton chants at the RNC convention were chilling. So was Trump's messianic rhetoric and his claim that he alone can save America from the abyss we're supposedly facing. And as chilling as the echoes (or foreshadowing) you'll find in eyewitness accounts in Kempowski's book.

The parallels aren't exact, but Hitler historians say they're close--and that should alarm every patriot.

Lev Raphael is the author of The Vampyre of Gotham and 24 other books in genres from mystery to memoir that you can find on Amazon.