one point on the original subject (sorry, i am new at this, but bear with me and i'll try to make it interesting :), communism will never work and "uptopia" can never be acceived because of one major humnan flaw: greed. in Michael Walzer essay, "Spheres of Justice, a defense of pluralism and equality", he makes and interesting point about human nature.
to paraphase, if you take all the resources and distribute them evenly in the beginning of the day, and give everyine "equal" power in the government, by the end of the night, the wealth would have been unequally reditributed, cause a class conflict (due to some trading goods for wealth, other saving..... etc.....) and power will have been given back to the few (someone enivitably convince another to let him/her lead by a passionate speach).
however, this is not to say that socialism does not work. as where communism looks for the perfect uptpia, socialism acknowledges the fact that that ideal can never be accieved. in switzerland, there is a perfect example of socialism at work. the goverenment takes care of ALL medical needs (including pscycholocial and other non-conventional treatments) and ALL education (elementary to getting your Ph.D). even foriegn visitors that have injured themselves on swiss soil can recieve free treatment. however, the draw back that over 60% of what the swiss make goes directly to the goverenment.
the question, there in,no longer lies not in the ideals of old, but should be how much power does the government need.
to reply back to the question of S. Korea, yes, it is a "demmocratic" state, but socialism has been banned to practice (you can thanks the U.S.A...... study Korean history, it's interesting....) because of the war with their nothern brethern. yes people, the Koreans are technically still at war with each other.