The war broadened Monday as Russian troops moved beyond rebel provinces into Georgia proper.
Georgian President Saakashvili called for international mediation over the breakaway region in a conflict some see as East vs. West.
After weeks of escalating skirmishes with South Ossetia, Georgia moved to regain control of the enclave. Russia responded by sending in tanks.
Standoffs over Georgia and a US missile-defense shield stem from one main irritant: Moscow had no hand in designing global security after the USSR collapsed. Medvedev wants to fix that.
The Democratic presidential nominee, who delivers the sole public foreign policy speech of his overseas tour here Thursday, was dubbed 'president of the world' by Der Spiegel.