The Gathering Storm, written by Churchill immediately after the war with all the documents of both sides, provides a masterful analysis of what the war really was about. In chapter 15 "The Rape of Austria" he quotes the protocol of Hitler's directive to the chiefs of the armed forces. Germany must have living space. It could be best found in Eastern Europe - Poland, White Russia, Ukraine. To obtain this would involve a major war and incidentally, the extermination of the people living in those parts.
Neurath, Fritsch, Blomberg, the General Staff were all alarmed by this policy. On February 4, 1938 Hitler dismissed Fritsch. Blomberg fell out because an inappropriate marriage. The Fuehrer assumed both political and military powers, and almost immediately, Austria was annexed, then Czechoslovakia and half Poland. The extermination policy was fully implemented on the Jews, the weakest sector, while the preparations already in place to extend it to the general population.
Hitler meant what he said and moved very fast. Churchill warns us "not to look down the decent, well-meaning British leaders" - but I could not make sense of his reasons for why not to.
P.S.: Chamberlain et al tried to deflect Hitler's aggressiveness and waited, and waited, hoping that someone else - the Austrians, the Czechs, the French, the Poles, etc. - would resist and so let them enter the arena with Hitler already engaged in a war. In the end, that was what happened with the Russians forced to confront Hitler. Churchill did follow the strategy of his predecessors, of avoiding direct confrontation with the Germans and letting others - ultimately the Russians and Americans - to fight the war. Anyway, the war ended with Britain impoverished and exhausted.