Fantasy literature is often characterized as escapist. I think this misses the point. Fantasy is fundamentally concerned with power, and our relationship to it. The fantastic element in every fantasy is power of some kind, either existing in nature or in the protagonist or the antagonist. It may be power of many different kinds, but it is always power, and with that power comes both danger and possibility.
I suggest that there are two major branches of fantasy, which I will call the lapsarian and the Promethean. They differ in how they deal with the dangers and possibilities of power.