...Let's start with the Air Nomads. Air, as an element, is a peaceful element by nature, without offensive attacks. It is also flighty, freewheeling, and epheremal. And yet, the head monks (at least, the ones at Aang's Southern Temple, where we actually get some sense of the hierarchy) are heavily weighted down by worldly concerns and worries, being so stern and serious that you can't imagine their jumping two millimeters into the air. Water is an element defined by its fluidity and organic nature. The Water Tribe society is defined by a stubborn adherance to obsolete and ancient traditions, marred by massive amounts of sexism. Earth is a strong, direct element; solidity and unpretensiousness are its key components. Ba Sing Se, despite my description of its directness-through-deception earlier, is still a city run on complete indirectness and sneakiness. And then there's fire, an element that runs on emotion and passion; yet, it's propagated by the Fire Nation, a country that we learn in this season is stifled and repressed, bogged down by propaganda and societal control.
In every case, we see how the men in control of each nation have gone completely against the natural characteristics of their elements, and we also see how their antagonistic constructions of their societies ultimately result in failure and collapse. (The Air Nomads push away the Avatar; the Water Tribe wastes time trying to prevent crucial allies from being trained; the Earth Kingdom's own conspiracies get used against it; the Fire Nation's societal control results in a populace glad to see its tyrant overthrown.) Kids may not have honed political minds to perceive every bit of what the writers and directors throw in, but these failures do communicate a concept to kids that they can easily latch onto: the adults who are in charge suck. And on that note, consider also how we have rather perfect examples of legitimate representations of the four elements from all four of the element-benders in Team Avatar, with Aang, Katara, Toph, and Zuko. They all exhibit the true tendencies of their elements, in their best and most honest ways. It gives an added resonance to their heroism; not only are they restoring the world away from an oppressive force, but their examples will set the standards for their elements and their nations, should they succeed.
