I see a lot of comments saying they aren’t. I’d disagree, but I agree they don’t have to be. The issue is most of the major powers in the world have opposed leftist governments anytime they show up. The ones that didn’t have a strong central power and cultural hegymony collapsed under the pressure. Any nation that had a weaker central power was either destroyed, couped, or undermined by the west.

There is nothing intrinsically authoritarian about leftism (really, I’d say it’s less authoritarian in it’s ideals), but authoritarianism is easier to hold together when outside pressures are trying to destroy you.