Smaug: Symbolism

I have always seen Smaug as the great dragon from Beowulf. Tolkien was a Beowulf enthusiast and it was he who first spoke for the merits of the Beowulf poem on its literary quality and narrative elements, as art and not just as a means by which we can learn about Anglo-Saxon history. He writes at length about this in his lecture,"Beowulf: The Monster and the Critics."
In creating Smaug, and in writing of Bilbo's interaction with him, Tolkien drew heavily from Beowulf and the stories reflect one another clearly.
In both stories a thief takes a golden cup from a sleeping dragon. The dragon wakes up and realizes that a piece of his treasure horde has been stolen. He searches everywhere for the cup and cannot find it. He finds the track of the thief and follows it, circling all around his trove. Then when he cannot find him, he returns to his mound and lies in wait, like a cat, eyes slit, murderously alert, for the thief to return.
Then sitting brooding there over how he has been wronged, he is overcome by his fury and wrath. Tolkien said himself that "...The episode of the theft arose naturally (and almost inevitably) from the circumstances. It is difficult to think of any other way of conducting the story at this point. I fancy the author of Beowulf would say much the same."
There is something very human about the dragon's actions and motivations in both stories. They are fascinating because you can relate to them.
John Gardner, in Grendel, which is his adaptation of the story of Beowulf as told from the antagonists point of view, also writes on this same dragon. Gardner takes it further though, and he works down to the character's essentially fatalistic worldview. He deals with what type of human thinking leads to a man becoming what the dragon in these 3 stories is. The Dragon in Gardner's Grendel, is an ancient creature, very much a miserly, mean-spirited old man. He knows everything there is to know. He sees everything from every angle and has determined through the obviousness of existence that there are no absolutes and no basis for truth except what you determine for yourself. The Dragon believes that existence is a chain reaction of accidents. No beliefs or ideoligies can be real. And in the end, after stripping absolutes away, the Dragon is left with nothing but his own immediate greed as the only substantive belief that consistently appeals to him. His last admonition in this story, his last advice to the Grendel, and to the audience is, "to find a pile of gold, and sit on it."
In Grendel, the Dragon becomes archetypical of nihilistic thinking. All the Dragon has left is his immediate greed. His desire for possessions in this, isn't the desire of the collector or the caretaker, that it is the gold's beauty or craftsmanship that appeals to him, but rather that other creatures might want to possess it, it is the far end of greed that wants something for the sake of preventing another from having it.

Another concept that has been put forth on the dragon in The Hobbit is that he could be seen as symbolic of the traditional relationship between evil and metallurgy. Perhaps even of industry, as these were themes that found their way into Tolkien's writing. Originally I was very taken by this idea and I wanted to make the dragon look like he was made of bronze that had patinad and that his scales were of metal that was rusting and flaking away. I like the idea that he literally did eat his gold and metal to give him armor, and that, like all things earthly, it was deteriorating away. His original skin and scales are long since gone, since he started introducing these heavy metals into his system, and now he must eat ever more and more as he ages, to keep his skin armored as the old metal rusts and flakes away faster and faster.

However, as much as this idea made arcs of lightning in my brain for being a cool visual metaphor, it simply wouldn't do for this image. The classic image is of a red dragon and in the end, I preferred a more personal, brooding, hateful greed that I see in the dragon to the more abstract notions of metallurgy or industry as the dragon being symbolic of. I may at some point go back and do a version of the dragon with metal flaking off him, but for now, I will stick with a more classic Smaug who is fascinating enough on his own.