Why Downvote Criticisms of Capitalism?

I have noticed an extreme bias as of late that Hacker News seems to downvote things that take a critical look at US established views of the word, specifically concerning negative views of the US's foreign interference in other nations as well as failures of capitalism associated with not just the US's bloody history, but in other countries as well. Is it kosher here to just downvote something you disagree with, or is the point of Hacker News to promote a certain viewpoint by downvoting anything that provides a thoughtful and novel critique of these subjects?