Game of Thrones' incredible success has turned it into the number one pop culture phenomenon today. It also proved that adult fantasy can be a prime-time hit.
But if we actually think about it, Game of Thrones is more of a fictional historical show than it is straight-up fantasy. Sure, magic, dragons and White Walkers appear in the story, but these are not what drives the plot.
Game of Thrones is a realistic story seeped in realpolitik and realistic main characters who at first do not even know that magic is coming back from its long slumber. And even when it does come back, magic is confined to the fringes: behind a huge wall or in another continent. Magic in Game of Thrones is actually a lot like a force of nature and less like a cliché perfect solution to the characters' problems. It's a tool, a weapon, and the fact that you can use it doesn't necessarily mean that you get to win. Case in point: Daenerys. Even though she has three dragons, she's not queen of the world, and they actually make it hard for her to be queen of Mereen.
Author George R. R. Martin set the stage for magic's place in the story in his first book of the series, called Game of Thrones, and the HBO show creators quickly followed suit. In the first season magic appears in the first and last scenes of the season (the White Walkers and the birth of the dragons, respectively) and in two more scenes in between (a zombie trying to kill the Lord Commander at the wall and Mirri Maz Duur "reviving" Drogo). Other than that, there is no magic in the story, as it focuses on the politics of a king's court of a medieval kingdom.
The major difference between our own Middle Ages and Martin's Middle Ages world is that in the latter the superstitions are actually true. Instead of our own made-up dragons and witches, these dragons and witches do exist.
Dragons, witches and other magic tools can be used for good, evil or anything in between. Dragons can slay thousands, enslave hundreds of thousands, or they can be used to free slaves. They have no redeeming qualities of their own, but are not malevolent either, they're just part of nature.
We can assume that the magical creatures that we know as White Walkers are not villains in this fifty-shades-of-grey world, since the only things we know about them are myths that those who fought them (humans) have been passing on to their children for the past 8,000 years. Since we ourselves know very little about who lived on earth 8,000 years ago and how they spent their time here, it's safe to say that
there are many misconceptions about the White Walkers.
If we look at magic as part of a different kind of nature, it could be that maesters in the future, turned scientists, will find some remains of these White Walkers, put them under the microscope and determine that they were some kind of extinct humanoids and that there were never any giant spiders, only exaggerated tales reminiscent of Big Foot , told by simple people who lived a long time ago.
Maybe these scientists will also examine long-extinct dragons and determine they were some kind lizards that produced heat in their stomach and they'll even find we share a common ancestor.
Basically, the less we know about magic the cooler it is. The mystic makes it more interesting. This is why the White Walkers and Children of the Forest have become more compelling than the dragons, but once we get to know their king on a first-name basis, they too will lose some of their charm.
We can look at magic in Game of Thrones through the lens of the God of the Gaps theory: in times past the ancient explainers of the world labeled as divine everything they could not explain. Even Sir Isaac Newton did it. Say, it used to be common knowledge that our sins pushed the gods to cause earthquakes, but we now know these have nothing to do with any celestial being, but rather with the shifting tectonic plates we live on.
That breaking of the spell could come to Westeros as well. The Magic of the Gaps could mean that magic will recede as the maesters offer explanations based on science, empirical evidence, and trial and error. That could be interesting, but a world with nothing but nature and science would probably make for far less interesting television.
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