I tried to read the Song of Fire and Ice by George R.R. Martin and couldn't get through much more than one book. The prose is rough, functional at best.

The TV series, though, I love. The first book ended up reading like an adaptation of the first season of the series, so closely did the two hew to each other back then. It made sense to me to find out Martin had worked as a Hollywood screenwriter for much of the 80's and part of the 90's.

What Martin does do well, and what makes Game of Thrones more fascinating than much of the fantasy series out there, is delve deeply into realpolitik. Characters win or lose not so much based on whether they are good or bad in character as whether they're the smartest player in the political arena, the so-called "game of thrones." Thus we see many characters killed off in defiance of audience expectations. That's the part of the series that I love the most, beyond the high and increasing production values (a noticeable increase in quality after season one), beautiful locations (refreshing in this day and age of cartoonish digital backdrops to see the real world serve as the backdrop for so much of the series), and fun performances (there are some weak links, like Danaerys, but most of the lead performances are strong).

Martin also manages to challenge the audience's desire for clean moral judgments (with the exception of characters like Joffrey who seem horrific through and through).

Much of this comes out in a really good interview of Martin in Rolling Stone.

A major concern in A Song of Ice and Fire and Game of Thrones is power. Almost everybody – except maybe Daenerys, across the waters with her dragons – wields power badly.

Ruling is hard. This was maybe my answer to Tolkien, whom, as much as I admire him, I do quibble with. Lord of the Rings had a very medieval philosophy: that if the king was a good man, the land would prosper. We look at real history and it's not that simple. Tolkien can say that Aragorn became king and reigned for a hundred years, and he was wise and good. But Tolkien doesn't ask the question: What was Aragorn's tax policy? Did he maintain a standing army? What did he do in times of flood and famine? And what about all these orcs? By the end of the war, Sauron is gone but all of the orcs aren't gone – they're in the mountains. Did Aragorn pursue a policy of systematic genocide and kill them? Even the little baby orcs, in their little orc cradles?
In real life, real-life kings had real-life problems to deal with. Just being a good guy was not the answer. You had to make hard, hard decisions. Sometimes what seemed to be a good decision turned around and bit you in the ass; it was the law of unintended consequences. I've tried to get at some of these in my books. My people who are trying to rule don't have an easy time of it. Just having good intentions doesn't make you a wise king.
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Early on, one critic described the TV series as bleak and embodying a nihilistic worldview, another bemoaned its "lack of moral signposts." Have you ever worried that there's some validity to that criticism?

No. That particular criticism is completely invalid. Actually, I think it's moronic. My worldview is anything but nihilistic.
Some of your most contemptible characters are also among the story's greatest truth-tellers. One of the most riveting moments in the TV series took place in the Battle of Blackwater episode, which you wrote the script for, when Sandor says to Sansa, "The world was built by killers, so you'd better get used to looking at them."

Truth is sometimes hard to hear. Two of the central phrases are true, but they are not truths that most human beings like to contemplate. Winter is coming and Valar morghulis – all men must die. Mortality is the inescapable truth of all life . . . and of all stories, too.