Andrew refers to “true believers” in communism as followers of a religion in the unlamented USSR. Having lived there for two years in the mid-1980s (as a student, to be sure, but as an Armenian in Armenia, so I had a much better look at what was actually going on), I met only one person, the whole time I was there, who actually believed in communism, and he was a graduate student in Marxism, so I suppose he had an excuse. The spiritual void came (comes) from the fact that Christianity was effectively dead (not only because of communist oppression but also because of urbanization and the other elements of modernity) but there was nothing that took its place. The Bolsheviks early on tried to institute “red baptisms” and develop a body of alternative, non-Christian given names to create a genuine Marxist cultural/religious alternative to Christianity, but by the time I got there, no one believed in anything any more. In other words, there were no longer any significant number of true believers in communism, which is why the whole thing fell apart so quickly.