Most people think we can learn from history.
Consider the emergence of the Communist Party (Lenin, Trotsky, Stalin) and the National Socialist Party (Hitler) after WW I. These parties arose in response to the horrors of that war. Poison gas was unleashed, machine guns were used, as many as 60,000 men died in a single day in a single battle. The world, it seemed, was unhinged. Terrible things never before imagined were inflicted on the human race and the wisdom of the past seemed outmoded. Despair was the order of the day.
Enter Communism and National Socialism (an extreme form of fascism). Each promised its own utopia, a world better than the one revealed by WWI.
Vladimir Tismaneanu in a new book on Communism and fascism, The Devil in History, describes the 1917 Bolshevik revolution as follows: