The difference today is that I don't see any convincing motivation for Russian expansion. Black Sea ports would be useful strategically, but after that - what? What would the point of annexing the Ukraine and threatening Poland?

Imperial cultures are inherently aggressive because territorial gains are needed to prop up the self image of the emperor. (Unless that emperor is George Bush, in which case nothing at all can prop up his self image.)

The Soviets were aggressive because Stalin was a paranoid drunken psychopath and there was always shreds of a nominal ideology explicitly interested in bringing the workers' paradise to the rest of the world.

Maybe I'm being staggeringly naive, but I can't see Putin in the same mould. He looks to me more like a spook-trained CEO and mafioso and a wannabe Tsar. Georgia is about making the point that Russia is back in the game again - but it's a single sentence statement, not a threat to invade Europe.

Threatening Russia with exclusion from the G8 is - of course - the worst possible course of action, because it undermines that sense of Russian participation, and will only increase Russian paranoia.