Here's a good article from the LA Times on the strategic backdrop to the recent events in Georgia.

There's a core question of US foreign policy in play here that few seem to be discussing. And that is whether it is necessary to the vital interests of the United States, or even consistent with the vital interests of the United States (I'm dubious on this latter point), to demand a Russian sphere of influence which is coterminous with Russia's own current borders. That's the policy goal that is the backdrop of this whole conflict, writ large and small.