Most "Hitler" and "Nazi" comparisons are fact-free.
As noted above, once NSDAP aggregated power, they "quelled violence."  Violence in Germany was an outcome of unemployment, hyperinflation, poverty, homelessness, general debasement of the culture, and attempts of Bolsheviks to subvert German politics.  
NSDAP turned the economy around, achieved full employment, built housing for workers at affordable cost, re-instilled a sense of dignity and community cohesion.  These measures were implemented non-violently, and prevailed in Germany from early in 1933 until late in 1938, when the German diplomat was killed in Paris.

Take it from this German "horse's" mouth -- https://www.youtube.com/watch?v=9Eyt4ZZKJ1M
Catholics owe it to themselves to critically analyze what they read, see, and write.  Jesus died for the truth.

1 more thing:  " The Dark Valley" is biased. It fails to mention the massive propaganda campaign British carried on (see Thomas Mahl, "Desperate Deception"). more -