William L Shirer, “The Rise and Fall of the Third Reich” (1960).
Its available online, in paperback, and at your local library.

Its a classic, considered the most detailed and complete history of Nazi Germany,
written by a German-speaking American journalist who had access to all the Nazi documents captured by the Allies and used as evidence
during the Nuremberg war crimes trials. Shirer lived and worked (as a journalist) in Germany and made it out just before
we became involved. I can’t think of anyone better qualified to write about the times.

History doesn’t repeat itself, as Mark Twain reminded us, but sometimes it rhymes. Germany in the 1920s and 30s, was not the same as the USA.
The times were different, the nations were different, the political, culture and economic environment was different. But the similarities and the parallels
are hard to ignore. A proud and rich nation, suffering economic and military reverses, is desperate to be “Made Great Again”. A charismatic leader
arises, one who claims he has all the answers, and who has identified all the villains, the people who stabbed Germany in the back and betrayed the nation.
He will make the rest of the world respect Germany again, stop abusing and cheating it, restore it to its rightful destiny.

He skillfully outmaneuvers all his political opponents, on both Left and Right, by playing one off against the other, gets into power legally and constitutionally,
(but through a technicality in the election rules) and takes over a great, advanced, civilized and cultured nation with a proud history and rich culture. He then
leads it into barbarism and disaster. It took everyone by surprise, no one believed it could happen, and no one thought it could happen so fast.

No one knows if Trump is another Hitler. No one can possibly know that. Likewise, no one knows if America will become a Fascist dictatorship like
Nazi Germany was. But until a few months ago, I would have thought it was impossible, there were too many checks and balances in our system
to allow that to happen. But I can’t say that with any certainty any more. We’re on a mountain road with no brakes, and the throttle is stuck wide open.

And of course, Trump is just the tip of the iceberg. He may not have the makings of a Hitler, but he has made a lot of promises to people that
expect them to be honored. People who are counting on the old America of the 1950s and 60s to come back, people who are counting on him to make
everything just like it was before. Not all these people are poor and desperate, some are rich and greedy and powerful. They won’t take ‘no’ for an answer.
And he has awakened forces and ideas that have long remained dormant in our society. Even if he himself does not believe them all, he has exploited them to
put himself in power. Even if Trump dies tomorrow (of natural causes) these ideas have been set loose and they will not crawl back under the slimy logs and rocks they slithered out of.

This is not about Left or Right, Liberal or Conservative. I love my country, but this is something I’ve never seen in America before, and I’m a 70 year old fart who loves history.. We’re’in uncharted territory now, the undiscovered country. Shirer’s book is the closest thing to a map we’ve got.