Even though the Communists attempted to kill Christianity forever in the relatively short period of time they held sway, without the Russian Church, the savagery of the hundreds of years of assault on Christianity by Islam would have resulted in a far more horror filled world today...a world of islamic hell.
The life of the Church during 80 years of communism in Russia was hell on earth. The very fact that the Church and faith survived in spite of everything is a testament unto itself.