In an alternative reality, Franklin Roosevelt is assassinated, Nazi Germany levels Washington DC with a nuclear weapon, and the second world war comes to the worst possible end.
This alternative reality played out in the 1962 novel The Man in the High Castleand also on my TV last spring in the series of the same name, and oh man, if you're looking for something to bring you down, the opening credits will have you there in under a minute.
There is the whirring sound of an old black and white movie projector. In dim funereal light, a huge invading arrow marked Greater Nazi Reich rolls across a United States map from the east while Japan takes the west.
In a sky without light or warmth, smoke billows from an American fighter plane dropping in the sky behind the Statue of Liberty. Silhouettes of Nazi paratroopers fall across the faces of the Mount Rushmore presidents.
In the rubble of Washington, a fragment of the Capitol building remains. The world we loved, the world that won, is rent asunder as a fractured prisoner's voice gives the tenderest performance of Edelweiss.
That's all pretty horrifying. Now: what's for dinner? Forward we go to the 1960s as the credits fade.
In the Greater American Reich there is prosperity. The cars and Cave for the livery which is, of course, red and black, a giant swastika on the tail.
There are many swastikas, on many very tall buildings, and occasionally troublesome senior officers are pushed from the roof of these skyscrapers, because did you really think Nazis with Beach Boys haircuts would be kinder or gentler?
Who could live in such a world? Actually, if you're an Aryan-looking American, you're having quite the time: sophisticated cocktail parties, summer camps, happy, healthy children. Unless, of course, you are found to be not sufficiently racially pure; unless, of course, your child should develop an unacceptable medical condition. Then you learn how readily and unblinkingly this cordial, polite regime can send a person to their death.
What kind of monster does that and comes home and tousles his kids' hair? Here's a plot twist: what if the teenage son whose hair he tousles turns out to have a medical condition and must therefore die? Of course, that's how it always was with Nazis: regular people leading regular lives, captured in Hannah Arendt's perfect chilling phrase: "the banality of evil".
Meanwhile, in San Francisco, a brutal Japanese regime pulls ten people at random from the street and summarily executes them whenever someone dares to commit an act of subversion. We see how it feels for Caucasians to have their race regarded as inferior and are you paying attention to this, white supremacists?
Can such a world ever exist again? People try to hold an actual fascist rally here in New Zealand and a paltry few gather, and you take heart from that. But people with alarming things to say seem to be altogether more numerous when they find somewhere a little more anonymous. Their message may be coded, in words like 'globalist', or it may be more overt. Here, how about the guy in this Facebook photo holding a placard that reads: "White women are for making white babies."
When you host talk radio, you encounter a certain kind of caller talking in a slightly elliptical way, and you know they are choosing their words carefully lest you dump them, beginning with something about the international financial system, but then suddenly fulminating about "The Jews" in a way that is so full of hatred you can scarcely imagine anyone could own a heart so black.
The dangerous mistake is to assume that Nazi Germany was altogether exceptional. They were just exceptionally well organised. We have seen their same evil in Rwanda, in Myanmar, in the Balkans.
People defend their Brexit vote for high and low reasons, some compelling and some quite nonsensical but the EU was forged to ensure an enduring peace on a continent where millions had been killed or murdered. It's not easy to see why anyone would feel like wandering off in search of an alternative reality.