After all, it's not the "-ism" that kills, but the people who perform it. Why do anti-communism folks argue against Communism as an state not because of its impraticality but because it is EVIL, BORING, CRUEL? Simple! Because, that is the easiest way to cop out from a tough question. Divide the world into good and evil. No doubt I'm good? Good. Then they are Evil.
But then again, it is not always capitalists who use those sort of base 'cop-outs'. The seduction of the "good-evil" scenario is even more tempting than the snake who drove the couple from Eden. And many sections of the left are certainly no stranger to it. In Korea, the socialist movement is outlawed. For every single demonstration we have to arm ourselves against the police. The union of the workers were legalized only 13 years ago, and any protest against the government was instant jail for you. Many things have changed, but many things also remain. Under harsh reallities people often forget what theit "-ism" was supposed to do.
They tend to remember only the fight at hand. Then remains self-justification, violence, heroic but immature tactics and strategies which bring spectacular failure upon the movement itself. That's what the students' movement of Korea is currently suffering from.
To hold on to our critical insights, we must look at former experiments of communism fairly: their vices as well as their virtues.
Actually, a lot of people have been murdered in the name of "Communism" and "Socialism".
The burden and the task of clearing the name falls into our hands. Let us not forget that.