I am seeing a parallel to modern day socialists/communists. Despite hundreds of instances of real adherents to the philosophy really trying in earnest to achieve communism in a wide variety of cultures, geographies and situations, it never works. We know why it works and economists can tell you exactly why it doesn't work. Yet, every new case of communism's failure is chalked up to not being "real communism" or being "bastardized by dictators".