I tend to believe that zero sum thinking is more a symptom of lower educated, and lower socioeconomic regardless of politics. I think the poorer members of society, and often whole cultures whether left or right. The only difference between the two political spectrae is how they plan to go about getting a greater share, but in both instances they tend to believe that for them to gain someone must lose. I think enlightened parties from left or right can see that all can have growth, it's just a question of methodology and timelines that separates them.
