From what I've been told (certainly not an expert), people thought he wasn't serious at first. Then he took over the country and everyone was afraid of him. They also had a large brainwashing/ propaganda campaign to convince Germans to support them.
Given a choice, do you think Hitler would have taken to a book or off the cuff remarks and Twitter?
Also, how many terrorists are there which the US could assaninate? Multiply that with 10 to accomodate with a family and you may up with a number not far off from the 10000 Hitler proposed.
Hitler and the NSDAP was way more organized than Trump. The party had a well defined manifesto and their ideological bent was pretty clear. Hitler attempted to gain power through a coup before trying the legit route.
Certainly there is definitely some routes of comparison between the rise of fascism in 1920s/1930s Europe and the right-wing-populist Trump phenomenon. However, in my mind the past politician that best approximates Donald Trump is Silvio Berlusconi. ("You never know", of course, but at this time I think some of the right wing political groups in Europe are better targets for 1920s-30s European fascism comparisons.)
