What is the theme in Lenin's Tomb: The Last Days of the Soviet Empire by David Remnick?

Truth is at the centre of these stories. The concept of truth is a foreign concept to most Soviets. They have been lied to for their entire lives by nearly everyone, including their government, teachers and families. The entire Soviet cultural foundation was based on lies. All of the significant events and figures that shape the Soviet Union's modern identity, including the Bolshevik Revolution, the great founder Lenin, the brave leader Stalin and the Great Patriotic War, are all lies.