Treating all persons equally has not always been a hallmark of American behavior.
About the best we can say is that over the years we've gotten better and anyway, we were never as bad as Stalinist Russia or Hitler's Germany or Mao's China.
The Plot Against America, a six-part drama that premieres Monday at 9 p.m. ET on HBO, doesn't say we were. It does say our commitment to tolerance may be more fragile than we care to admit.
Based on the novel of the same name by Philip Roth, The Plot Against America suggests that the "all men are created equal" line in the Declaration of Independence has been, and quite possibly remains, less a bedrock principle than a matter for negotiation.
The Plot Against America makes this point by creating an alternate history in which aviator Charles Lindbergh wins the presidency over Franklin D. Roosevelt in 1940.
Lindbergh, by the late 1930s, had become a leading spokesperson for America First, an organization that wanted America to stay out of the looming Second World War.
Had America done so, Great Britain likely could not have held off Nazi Germany. Since Germany in late 1940 was still allied with the Soviet Union, that would have left most of the world in Axis and Axis-allied hands. A neutral United States would most likely have sought a peace treaty recognizing Adolf Hitler's domination.
The Plot Against America works with that general premise. But it does not frame itself as a documentary, a historical "what if." Roth instead builds a story around the family of the Jewish Herman Levin (Morgan Spector), who lives in a respectable lower-middle-class neighborhood in Newark, N.J.
Herman is happily married to Bess (Zoe Kazan), and they have two sons, the teenage Alvin (Anthony Boyle) and his younger brother Philip (Azhy Robertson).
Herman is a life insurance salesman and a good one. He's in line for a promotion to a job where he could make $75 a week, enough to move the family out of their apartment and into a house.
He finds a good candidate. Just one catch: They would be the first Jewish family in the neighborhood, and the vibes are a little troubling, like when some of the men at the local beer hall yell, "Go back to Delancy Street."
That's not one isolated drunk. A whole lot of folks in Newark, and America in general, think Lucky Lindy's got the right idea, that America shouldn't plunge into another meat grinder over in Europe just because all those Jewish folks want them to.
World War I isn't a good selling point for entering another world war. But as Herman and his friends note, this time there's a little more at stake. Hitler has already made it clear he blames Jews for everything, even if it's not evident yet what he's already planning to do about that.
A friend of Herman's notes that a majority of Americans consider Jews "different" and think someone should keep an eye on them.
Herman and his friends also think that Roosevelt, while they like him, isn't pushing back hard enough against Americans who shrug off Germany's military conquests and crackdowns like Kristallnacht.
Against this increasingly tense international backdrop, Bess's sister Evelyn (Winona Ryder) worries that she's turning 30 and doomed to became an old maid. She has just been dumped by her latest married boyfriend when she runs into Rabbi Lionel Bengelsdorf (John Turturro, top).
Evelyn and the rabbi will become pivotal characters as Lindbergh won the presidency and takes America in a very different direction than it went in real-life history. What makes The Plot Against America particularly troubling is that it suggests hearts and minds can be incrementally taken to places they may not realize they're going.
While President Lindbergh may be doing the primary thing most Americans want, which is to stay out of the war, the consequences of that decision and other seemingly minor or unnoticed lower-level actions can cumulatively reshape America.
The Plot Against America isn't a prequel to the just-concluding Amazon Prime series Man in the High Castle, which supposes a German conquest of the United States. But it explores the same broader question of how strongly Americans would hold to our higher principles if it became easier to abandon them.
It's not always an easy show to watch. Watch it anyway.