"Whatever the larger goal of Russian President Vladimir Putin’s armed intervention in Syria, it has succeeded in distracting the world’s attention from his ongoing aggression in eastern Ukraine. In his half-hour speech at the United Nations earlier this month timed to reach a prime-time Russian audience, he spent only a minute on the Ukrainian conflict, focusing instead on Russia’s constructive role in the Middle East. Putin’s rhetorical redirection is not surprising. The Kremlin’s war in Ukraine is turning into a quagmire. Militarily, it is a stalemate — which, given the vast imbalance between Russian and Ukrainian capabilities, amounts to a...