Following unmitigated hate speech that incited enough people's base instincts to back a madman. The rest is history.
Germans
chose to follow Hitler. You're missing that. Hitler didn't put a gun to their head (until much later).
The term Hate Speech can be construed to mean anything. Who defines it? Ever watch Christopher Hitchens? He absolutely destroys this notion of censored speech in a free and open society. Bureaucrats determine whats hate and what's not. Class warfare/soak the rich could be considered hate speech. Calling someone a racisist could be considered hate speech. Many other Left-wing themes you guys base your ideology around could be considered hate speech (global depopulation, anti-Christian, pro-abortion).
The Founders were much smarter then you or I, and protected all manner of speech because its the least desirable, most offensive speech that needs the most protection. Especially in times of war and political change, it's the minority opinion that becomes scorned and criminalized as 'traitorous' that needs to be heard the most.
Like when Bush inferred Americans as traitors who wouldn't support the patriotic act, and spying and the wars. And Americans came out in support of the Constitution and freedom. The Right tried very hard to smear them as anti-American, and terrorist sympathizers. For defending freedom.
Ironically it was the Left who came out for the Constitution. And now when their boy is in power, they don't give a shit about it. Neither does Obama. This is why you and your ilk never have the moral high ground - your blatant hypocrites who only give a shit about raw power. Principles are only invoked to make political hay, when you don't have the power. When you do, it all goes out the window.