Could Adolf Hitler have been stopped?
Unlikely. The German people were eager for radical reform, if it
hadn't been Hitler it would have been a communist dictator. Thats
not very true at all. The United States had resorted to
Isolationsim, Russia was worrying about the aftermath of the
Revolution, ect. Nearly every one was worrying about themselves and
not paying attention to finer detail. Hitler written out his exact
plans in Mein Kampf. And yes, Germany was eager for reform, but
they had no way of protecting themselves for what was to come. The
impact of World War I was a major reason for Hitler's easy rise.
The German General Heinz Guderian states in post war interview that
had the Allies intervened militarily in 1935 when Hitler
remilitarised the Rhineland that the Germans would have been
powerless to resist. And of course with the benefit of hindsight
that is easy to see, the fact was the allied leaders (Britain &
France primarily) lacked the backbone to do anything at all. They
were busy disarming to try, ostensibly, to avoid war. Laudable that
this was, it remains impossible for these leaders to have been able
to realistically think that Hitler was quite the despot that
history shows us. Who could have possibly believed the worst ?