I did write about Mill's opinions on socialism here on ET.

We are too ignorant either of what individual agency in its best form, or Socialism in its best form, can accomplish, to be qualified to decide which of the two will be the ultimate form of human society.

If a conjecture may be hazarded, the decision will probably depend mainly on one consideration, viz. which of the two systems is consistent with the greatest amount of human liberty and spontaneity.

I believe he correctly predicted the way in which "real socialism" would fail in this respect in the 20th Century by degenerating into totalitarianism.

En un viejo país ineficiente, algo así como España entre dos guerras civiles, poseer una casa y poca hacienda y memoria ninguna. -- Gil de Biedma