100 years of Communism

How strange that teachers and professors do not teach this: 1991 comparison of per-capita GDP of communist and non-communist countries:

(source)

Communism robs a nation of 80% or more of its wealth.  You don't even have to talk about the body count, just the impact on the economy.  Add in the destruction of the environment: Chernobyl, the Aral Sea, the Three Gorges Dam, etc and it is a damning indictment of the modern leftist's world view.