Hitler was the leader of German and the Nazi party after WW1. His major accomplishment was being the founder of the Nazi party. One problem he saw in Germany after WW1 is that they are all taking the blame for that war starting. He didn't like that and also he saw that the German government was failing to it's people so he deiced to make a new party know was the Nazi party. He said "Whenever I think of this attack, my stomach turns over". In that quote is talking to Guderian about the tank warfare.