(CNN) -- A superpower needs a super attention span. Unfortunately, Americans seem to take little interest in the troubles of the world around them, even when those troubles threaten soon to vex Americans themselves. Americans fought two world wars -- and faced nuclear annihilation in a protracted Cold War -- to defend the freedom of Europe. In the thrilling days of 1989-91, four generations of American sacrifice were magnificently vindicated. The communist regimes of central Europe collapsed. The Soviet Union itself broke apart into smaller and less threatening pieces. For four centuries, the rulers of Russia had sought security for themselves by dominating first their own people, then their neighbors, then their neighbors' neighbors, then their neighbors' neighbors' neighbors ... until their power extended from Berlin to the Pacific Ocean.
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David Frum: Democracy failed in Russia and a top officer of KGB, Vladimir Putin, became president
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Frum: Putin and his coterie want to resurrect Soviet Union and want to keep Ukraine in thrall
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Frum: Ukrainians want to enter EU and lessen dependence on Russia; Putin fighting to stop it
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He says Ukrainian protests met with brutal suppression; time for U.S. to pay attention
Ukrainian independence liberated not only the @placeholder people, but all Europe.
Russia without the nearly 46 million people and vast natural resources of the @placeholder is a large and powerful country, but it is no superpower.
A @placeholder that reintegrated Ukraine would possess the power -- like the Soviet Union of old -- to intimidate and bully democratic Europe.