1917 and surrealism of Russian history. October has already come

The role of the 1917 revolution in world history is evaluated by its researchers ambiguously. What was it? "Historical mistake" of extremists who reached the power, or a military coup committed by the Bolsheviks based on the revolutionary units of the army and navy? Or maybe it was, in the words of N. Berdyaev, "reckoning for the sins of the past"?
The book of the famous writer and historian A.G. Ushakova is not the truth in the last instance, and not the verdict, the main task is that each reader has a desire to understand what happened and is happening to our country. According to the author, there will be a story that does not teach anything, but brutally punishes for unwillingness to learn from her.
And now ahead, in the seventeenth year!