A more accurate statement would be between centralization and decentralization: aka: Peter the Great was a huge centralist. Catherin was a decentralist (moderate), her son Paul was a huge centralist, followed by a weak and decentralist Alexander I. Nicholas I started as a decentralist but after revolts became a very strong centralist. Alexander II was a huge decentralist, pushing a lot of power to the Zemstovs (local assemblies). He was killed by socialists and his son Alexander III was a massive centralist. Nicholas II was a weak centralist fighting against massive decentralists. Lenin started out as a moderate centralist and became a weak decentralist (NEP) followed by Stalin a massive centralist. After Stalin came Khrushchov who was so decentralist he forced a lot of the bureaucratic heads to move their offices out of Moscow and into the country side. For this, he was eventually over thrown by strong centralists.
Eventually they lost power to Gorbachov a weak decentralist who lost power (and the SU) to Gorbachov, such a massive decentalist that the nation almost fell apart. Now it's swung back towards centralism under Putin.
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