An interesting critique of GRRM's A Song of Ice and Fire that argues that the "problem" with GRRM's vision is that it's realistic rather than idealistic, and that GRRM himself is consequently a nihilist.

The critic (Sargon of Akkad) is wrong both in his diagnosis and in his blanket championing of idealism (he cites explicitly and approvingly Woodrow Wilson’s disastrous foreign policy). GRRM is an idealist who lives in a world where mythmaking has been unmasked as propaganda.

The "nihilism" of ASOIaF isn't the result of "realism," but is, in fact, the ultimate end point of all idealism when it runs up against reality.

Right wing thinkers who ignore Machiavelli, McKinder, Sun Tzu, etc. in favor of idealism are making the same mistake as their left-wing counterparts, for the same reasons, and will invariably run revolutions that meet the same ends.

It's not "cynicism" to look frankly at the darkness of the human soul and attempt to direct it toward productive ends--it is, instead, the kind of realism that was the engine of the three greatest empires in history (England, America, and Rome). Nor is realism incompatible with moral order--it simply recognizes the nature, place, and limits of morality.