This is what the great fantasy writer has to say about it:
This is not a list of the “best” fantasy or SF. There are huge numbers of superb works not on the list. Those below are chosen not just because of their quality—which though mostly good, is variable—but because the politics they embed (deliberately or not) are of particular interest to socialists. Of course, other works—by the same or other writers—could have been chosen: disagreement and alternative suggestions are welcomed. I change my own mind hour to hour on this anyway.

The list has its surprises:

Ayn Rand—Atlas Shrugged (1957)

Know your enemy. This panoply of portentous Nietzcheanism lite has had a huge influence on American SF. Rand was an obsessive “objectivist” (libertarian pro-capitalist individualist) whose hatred of socialism and any form of “collectivism” is visible in this important an influential—though vile and ponderous—novel.

And its delights...

Mikhail Bulgakov—The Master and Margarita (1938; trans. 1967)

Astonishing fantasy set in ’30s Moscow, featuring the Devil, Pontius Pilate, The Wandering Jew, and a satire and critique of Stalinist Russia so cutting it is unbelievable that it got past the censors. Utterly brilliant.