It should be noted the press is not entirely on the side of Saakashvili. See this Time piece, which is very critical:

Plainly, the offensive was a gamble, because Saakashvili should have had little doubt about Moscow's readiness to defend the separatists. Moreover, NATO officials had repeatedly warned the Georgian government against launching any attempt to resolve the dispute through military means. Still, he pressed forward.

Russia's initial response was to convene an emergency session of the U.N. Security Council, hoping to pass a resolution calling for an immediate ceasefire between Georgia and South Ossetia. But the Russian draft resolution was contentious. The United State and others objected to language that appeared to exempt Russia from condemnation over the use of force.

Saakashvili is appealing for Western support, based on international recognition of South Ossetia as sovereign Georgian territory. "A full-scale aggression has been launched against Georgia," he said, calling for Western intervention. But given NATO's previous warnings, its commitments elsewhere and the reluctance of many of its member states to antagonize Russia, it remains unlikely that Georgia will get more than verbal support from its desired Western protectors. Saakashvili appears to have both underestimated the scale of the Russian backlash, and overestimated the extent of support he could count on from the U.S. and its allies.

I do not see Time writing this when there is an active effort from the White House to move towards intervention.

My guess, based on the media response and its own statements, is that either the White House really was not informed beforehand, or it cut Saakashvili loose.