A wonderful blog I've just come across, On Dover Beach, noting this significant anniversary observes not only is communism ugly, politically and morally but aesthetically, too and offers a good explanation why: the absence of God.
I think it's because everything true and beautiful comes from God. Cut yourself off from Him, study to forget Him, and after a while, all you can make are things that are temporarily useful. While the memory, the thought-habit, of God's primary creation is still present, as it is the West now, things of lesser good can still be made; but soon, all effort turns to things that can be used for domination. And not just domination of the State over individuals, but also the domination of the weak over the weaker (e.g., abortion on demand, and the killing of human embryos for potential disease therapies). This, after all, was what Lucifer chose when he rebelled: better to reign in Hell, as Milton so colorfully gave him to say -- where I can dominate everyone and everything around me with my own demi-god inventions, according to my own lights and rules -- than serve in Heaven. Than acknowledge that God is God, and I am not.
Read it all, this guy is good. If hell is indeed the absence of God, communism offers visual manifestation of it.