Revolting plans, terrible fights against religion, churches shut and blocked, priesthood massacre. Barbarous cruelty of Soviet authorities and J. Stalin. Alternative opinion: the country needed to make a leap into industrial age. Prejudice and brakes had to be removed. The authorities had to give the population an incentive to work, whereas the religion was an archaic remainder of the tsar age. The elimination of illusions and sheer realism—that's what the late-blooming country needed to catch up with the strongest European countries.
Wikipedia says: On 5 December 1931, by order of Stalin's minister Kaganovich, the Cathedral of Christ the Saviour was dynamited and reduced to rubble. It took more than one blast to destroy the church and more than a year to clear the debris from the site. The original marble high reliefs were preserved and are now on display at the Donskoy Monastery (see the photo). For a long time, they were the only reminder of the largest Orthodox church ever built.