On January 21-25, 1998, Pope John Paul II visited Havana. His visit elicited such a wave of popular enthusiasm that it became obvious how little the Communist Party of Cuba managed to achieve in terms of combating the religious feelings of the Cuban people. Things were very different in the Soviet Union where the majority of the population let go of their religious allegiances with a notable ease. In the 20ies and the 30ies, people whose families seemed to have been deeply committed to the Russian Orthodox Church for centuries happily destroyed cathedrals and burned religious images.
One of the reasons for this difference in the religious attitudes of the Soviet people and the Cubans lies in the history of how they came by their religious affiliations. In Cuba, Santeria integrated Catholicism, Yoruba religion and the traditions of the indigenous peoples. The resulting mix helped people experience catholicism as their own, since most of concepts that have currency in Catholicism could be easily explained in Santeria terms.
The Slavic people came by their Christianity in a very different way. In the late Xth century, Vladimir the Great, the grand prince of Kievan Rus, started casting about for a religion to which he could convert his people. He approached not only Christians but also Muslims and Jews with a request to be told more about their religions with a view to a possible forced conversion of the Slavic people to one of them. Islam didn't work for him because, even though it allowed one to have several wives (a huge bonus for Vladimir), it prohibited alcohol, and that was definitely not going to be acceptable. The Jews were rejected because Vladimir didn't feel like allying themselves with people whose loss of their land signaled, in his eyes, that they had been abandoned by God.
So Christianity was chosen and mass baptisms of Slavic people were conducted. Of course, nobody made any efforts to explain to the people what was going on, why their pagan rites had to be abandoned, the statues of their gods destroyed, and a religious tradition that was completely alien to them had to be accepted and practiced exclusively. Slavs were converted to Christianity through mass killings. Entire towns were burned alive for refusing to accept this alien religion. Christian churches were purposefully built on the sites of pagan cemeteries. This, of course, made any genuine popular acceptance of Christianity quite impossible.
For centuries to come, Christianity would be a huge divisive force in society where the rich and the powerful accepted it as their religion while everybody else still practiced pagan rites and only went through the motions of Christian traditions to avoid persecutions. Paganism was not only a system of beliefs for the Slavs. It was a way of finding a shared language with the nature that surrounded them and the climate that wasn't making their lives easy. Forced Christianity took all that away and gave very little in return. Until the Revolution of 1917, Russian Orthodox Church was a profoundly oppressive force in society that celebrated its extremely expensive rites with great pomp and allowed its officials to live in incomparable luxury. (As we all know, these folks picked up right where they left off after the fall of the Soviet Union.)
People, in the meanwhile, still retained a worldview that was deeply pagan even though they might not have remembered this word any longer. Prevented from venerating their pagan deities, they developed an attitude where the political leaders of the country were treated as such substitute deities. Today, this attitude towards politicians in charge of the country still persists in those of the Slavic countries where Christianity was imposed in this uninspired and violent way.