Faced with the threat of a U.S. strike on Syria, Russian President Vladimir Putin has a dilemma: allow U.S. missiles to hit Moscow's ally without a response or risk a military clash with the United States.
If driven into a corner by a U.S. attack, Putin will be unlikely to sit back. Inaction would threaten his hard-won gains in Syria, dent Russia's prestige and erode his tough-guy image.
"It's our president who decides the fate of the world!" ultranationalist leader Vladimir Zhirinovsky declared on Russian state television.
During past crises in recent years, Putin has responded by overturning the chessboard.
When Ukraine's Kremlin-friendly leader...