PRESIDENT VLADIMIR PUTIN, his bitter resentment at the Soviet empire’s collapse metastasized into seething Russian nationalism, has marginalized the political opposition, muzzled dissidents and intimidated independent voices in civil society. In prosecuting his widening war in Ukraine, he has also resurrected the tyranny of the Big Lie, using state-controlled media to twist the truth so grotesquely that most Russians are in the dark — or profoundly misinformed — about events in their neighbor to the west.