(CNN) -- I recall being an undergraduate in Russian Studies at Amherst College when the Soviet Union invaded Afghanistan in December 1979. I was flabbergasted when then-President Carter initially expressed surprise that Leonid Brezhnev and his cronies decided to undertake that ill-fated adventure. Just the little I knew of Soviet history at that time led me to conclude that one should never be naÃ¯ve about Russia. Wisely, the Carter administration soon implemented a wide-ranging and powerful set of sanctions against the USSR. By comparison, Barack Obama is now making Jimmy Carter look like Attila the Hun with a series of empty threats and "too little, too late" punitive measures against Putin's Russia.
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Andrew Kuchins: Obama and allies have issued empty threats at Putin
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Kuchins: Despite Russia's annexation of Crimea, Obama's responses are weak
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He says since Putin has met no push back for Crimea, why would he stop there?
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Kuchins: Putin may ruin Obama's legacy by further encroaching Ukraine
On February 28, President Obama warned @placeholder not to take military action against Crimea, and if he did so, serious "costs" would be imposed.
Putin will likely meet his own end if he miscalculates in @placeholder.