Authoritarianism is the common denominator; only the details vary.
If you think you have the best idea, the natural next move is to force everyone to follow that best idea, no room for disagreement or alternatives.
This pops up everywhere, everywhere ideology is involved in decisions.
Stalin, Mao, Castro, Hitler- they were all 'idealists.'
They were in it to improve the human (or some subset thereof) condition. And they weren't going to let anyone get in their way of making things better!
It is worth a watch https://www.youtube.com/watch?v=kf-bSAnW_E0 but it itself is a somewhat simplistic take.
You can't make an omellete without breaking a few eggs, after all. That was Lenin, supposedly.
edit: spelling of "one"
Which is why they all failed.
I bet it's related to the tendency for narcissism where you believe that you alone have all the right answers.
The "political compass" has two dimensions: left/right horizontally and authoritarian/libertarian vertically.
Unfortunately "political compass" is also for the quadrant memes: https://en.meming.world/wiki/Political_Compass (which has some good commentary on the compass and great examples).
And there's the Nolan Chart: https://en.m.wikipedia.org/wiki/Nolan_Chart which is even more confusing. The word "liberal" is not used in New Zealand much, although perhaps the US meaning is taking hold. Also centrist here is unclear so the Nolan Chart makes no sense to me.
