The modern left are the spiritual heirs of these people.
On May 10, 1933, Nazis in Berlin burned works of Jewish authors, and the library of the Institut für Sexualwissenschaft, and other works considered "un-German".
73 years later, rather than burn books they consider "un-liberal", lefties abuse Amazon's reader feedback system to suppress them. They post comments on books by conservative authors most haven't read to cut their Amazon star ranking. This isn't Amazon's fault - their system adds a lot of value and assumes good faith.
Michelle Malkin has the full story, with examples here and here.
I've ordered both books & when I've read them will share my opinions with Amazon.