History does repeat itself. Never exactly -- there are always enough differences in the details that people who are determined not to learn anything from the past can find an excuse.
But history shows patterns precisely because human beings don't change.
After the First World War (then called the Great War), Britain and France were exhausted. They had triumphed -- barely -- but they had left more than a million dead soldiers on the battlefields.
Germany suffered nearly as badly. But the German people did not feel defeated. They were ripe for Adolf Hitler to come along and tell them that they had really won the war, except that they were stabbed in the back by traitors at home.
So as Adolf Hitler began to rearm Germany, preparing for a rematch, he found an enemy that simply did not want to fight any kind of war at all.