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With President Barack Obama's trip to Moscow on Monday, you might expect Russia to avoid stirring up any trouble. Yet the Russian media are now abuzz with speculation about a new war in Georgia, and some Western analysts are voicing similar concerns. The idea seems insane. Nonetheless, the risk is real.

One danger sign is persistent talk of so-called Georgian aggression against the breakaway regions of Abkhazia and South Ossetia, which Russia recognized as independent states after the war last August. "Georgia is rattling its weapons . . . and has not given up on attempts to solve its territorial problems by any means," Gen. Nikolai Makarov, who commanded Russian troops in Georgia in 2008, told the Novosti news agency on June 17. Similar warnings have been aired repeatedly by...