I just had a thought. Leftism isn’t a real thing. It exists only in the minds of leftists. Human nature and math both preclude the existence of the leftist utopia in reality. That much is obvious. However, that doesn’t explain why there are still leftists.
Many leftists, I believe, don’t actually believe in what they claim to; they just want power. However, there are still people (i.e. the “sheeple“) who don’t benefit from leftism, and in fact suffer because of it. And, yet, in many cases, they want more of it (such as the “Idle No More” movement, a movement among Aboriginal Canadians, a group that has been severely impoverished by leftism). My hypothesis is that, because the reality doesn’t at all resemble the leftist utopia they imagine, they don’t view the policies that got them there as leftist policies. So, they think in this way: leftism produces result A, but the existing policies produce result B, and therefore the existing policies cannot be leftist. However, “leftism produces result A” is according to the narrative (or “theory,” if you can call it that, which you can’t really), not reality.
Basically, this is just a slightly different version of the old explanation for leftist behaviour that suggests leftists pay attention to their narrative and not to reality. It just illustrates their backwards thinking more.