Robert Kagan, author of The Return of History and the End of Dreams - an excellent book - on the ambitions of Mr. Putin:
... This war did not begin because of a miscalculation by Georgian President Mikheil Saakashvili. It is a war that Moscow has been attempting to provoke for some time. The man who once called the collapse of the Soviet Union "the greatest geopolitical catastrophe of the [20th] century" has reestablished a virtual czarist rule in Russia and is trying to restore the country to its once-dominant role in Eurasia and the world. Armed with wealth from oil and gas; holding a near-monopoly over the energy supply to Europe; with a million soldiers, thousands of nuclear warheads and the world's third-largest military budget, Vladimir Putin believes that now is the time to make his move.