In an extraordinary development Thursday, the Obama administration announced a series of sanctions against Russia. Thirty-five Russian nationals will be expelled from the country. President Obama issued a terse statement seeming to blame Russia for the hack of the Democratic National Committee emails. "These data theft and disclosure activities could only have been directed by the highest levels of the Russian government," he wrote. Russia at first pledged, darkly, to retaliate, then backed off. The Russian press today is even reporting that Vladimir Putin is inviting "the children of American diplomats" to "visit the Christmas tree in the Kremlin," as...