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Last Wednesday in Moscow, the remaining illusions the Obama administration held for cooperation with Russia on the Iranian nuclear program were thrown in Secretary of State Hillary Clinton's face. Stronger sanctions against Iran would be "counterproductive," said Russian Foreign Minister Sergei Lavrov, just days after President Dmitry Medvedev said sanctions were likely inevitable. This apparent inconsistency should remind us that Mr. Medvedev is little more than a well-placed spectator, and that Prime Minister Vladimir Putin, who discounted sanctions in a statement from Beijing, is still the voice that matters.

This slap comes after repeated concessions—canceling the deployment of missile defenses in Eastern Europe, muted criticism of Russia's sham regional...