I'm pretty much with JJB on this, although with the slight adjustment that I think, in particular, what happened in the thirties leading up to the Big Ugly is something everybody should know. It's maybe the biggest "cautionary tale" lesson ever.
In the decades since, people have wondered and asked "those terrible German people, how could they bring this on the world by supporting the Nazis and Hitler?". They don't understand how it happened. How easily it happened.
It short form, it happened because people saw what they wanted to see. In a country that was in a real mess, a culture that put high value on ideas like strength and effeciency and rigid order thought they saw a bunch who would bring them. They didn't think about the costs, and couldn't, or choose not, to see that their "mighty leader" was just some little Austrian jerk with a cheesy moustache and the nastiest bad attitude imaginable, who couldn't sell his crappy paintings. With a bunch of goons behind him.
By the time maybe some of the regular folks started to grasp something was wrong, I suspect the average German probably just tried to go about their daily business and steered clear of gangs of blockheads in brown shirts. By then it was probably too late for most. They were stuck in it.
People like LR helped sell what seemed like the shiny happy version to the population, and the mass delusion took hold. By the time the average guy started waking up from it, it was probably too late to even quietly suggest to your buddies at work that maybe something was wrong, without risking a bullet in the head soon after.
I don't really know a lot about Leni Reifenstahl, but from what I gather, it was a story where moral choices got shuffled to the side, with maybe a little self delusion to serve the short term, for the idea "hey, I could really get a good gig here". I'm a little curious to know more about how she rationalized things before, during, and in years after.
There are probably a bunch of stories like that. Ferdinand Porsche would be another one. The Volkswagen Beetle was Hitler's baby that he got Porsche to realize, and Herr Porsche happily played along because it seemed like the perfect chance to pursue some of his own concepts. Apparently he just shrugged and took the attitude "I'm not interested in the politics", and made a deal. This also extended to another branch of Hitler's propaganda machine.
To demonstrate the "new Germany" technological superiority, Hitler and his boys threw massive support into motorsports, which led to the prewar Grand Prix racing (precursor to today's Formula One) being dominated by Mercedes and Auto Union. You might not know the name "Auto Union". That's understandable. It's now Audi, and today's Audi-Porsche-Volkswagen group has its roots back then. Got a Volkswagen? Pop the hood. Look around the engine bay, and somewhere on cast parts you'll find a logo of four interlocking rings, the Audi logo. You can look at old photos of the Auto Union racers in the thirties that fed the Nazi propaganda machine, with that same logo on the nose. I have trouble seeing a silver Audi TT on the road today without mixed feelings. A lot of otherwise good people worked in all that, saying some variation on "I'm just an engineer" or "I just want to race and win", and the Nutsee promo machine got the PR benefits.
Of course Doctor Porsche also got spanked for this stuff after the war, spending some time in a French dungeon of a jail cell.
Hey, while I'm on it, let's not overlook something conveniently forgotten over the years, which was that Henry Ford, in the thirties, thought that these National Socialist guys over there in Germany were just a great bunch, and he was all for them. Even offered help and advice for the Porsche/Nazi "People's Car" project and invited the boys over for a little tour of the place in Dearborn. Even less often discussed is that the Bush family fortune, apparently, didn't actually start with the oil business, the big money that led to that business was Dubya's grandpa being one of the people who arranged financing deals for a little "seed money" to the German National Socialist party in the thirties, which paid back large dividends.
Sorry for the long post in something a little OT in this forum, but the point is that we can look at stories like Leni Reifenstahl, and there are a couple points to get from it. That it can be really easy for people to overlook ugly stuff happening right in front of them in favor of grabbing a chance at Big Career Advancement for themselves, and not see the big repercussions in the future; and second, that in the future, excuses like "oh, well, it had nothing to do with me, really, I was just doing a job" don't tend to be excused and looked upon with tolerance and kindness. If something that seems like an opportune gig comes up, but something bothers you about it, maybe you should not too easily convince yourself that "it's nothing, besides, it's just a gig, I'm just doing a job, it's not for me to decide if there's something bigger that's wrong here".
(In the years since WW2, this has sometimes been called "the Good German" syndrome)
JLE