From Michael Dobbs' excellent and even-handed piece in the WaPo:
It is unclear how the simmering tensions between Georgia and South Ossetia came to the boil this month. The Georgians say that they were provoked by the shelling of Georgian villages from Ossetian-controlled territory. While this may well be the case, the Georgian response was disproportionate. On the night of Aug. 7 and into Aug. 8, Saakashvili ordered an artillery barrage against Tskhinvali and sent an armored column to occupy the town. He apparently hoped that Western support would protect Georgia from major Russian retaliation, even though Russian "peacekeepers" were almost certainly killed or wounded in the Georgian assault. It was a huge miscalculation.
Putin's aggression was massively disproportionate, but the US definitely played into his hands by championing Saakashvili so hubristically. And I didn't know this:
It is true that he has won two reasonably free elections, but he has also displayed some autocratic tendencies; he sent riot police to crush an opposition protest in Tbilisi last November and shuttered an opposition television station.
Wise leaders show a steady hand and a calm posture in dealing with these events. McCain has done neither. Once again, the most impressive figure in all of this has been Robert Gates.