How does history stop history being repeated?

Well, sometimes history can stop history from being repeated as the people involved can see the consequences from it. An example of this is World War 2; people saw that they gave Hitler too much power and so from then on started wanting to restrict governments in some way. Though there was still totalitarian governments, governments wanted to help the independence of other countries. Also, they wanted there not to be any more antisemitism and no more war and so created the United Nations, which worked and still works better to prevent was than the League of Nations did and they let the Jews have Israel though that did have consequences as well.