Understanding Hitler and the Germans

The inner logic of the Nazi movement and the Third Reich is inseparable from that of Hitler: one cannot understand one without first examining the other.

How did an uneducated, uncultured individual, whose life up to the age of 30 had been a series of failures, manage to impose his will on a great modern country before dragging it into a military and moral catastrophe unique in history?

The answer to this question begs another: Can what happened in Germany happen again?