Because Adolf Hitler used the Jews as a scapegoat for post-WW1 financial troubles and used phrases like “Bolsheviks” and “Marxism” to convince right leaning German citizens that the Jews were not only the cause of their problems but actively working to destroy their way of life.
This instilled a belief system in the fundamentalist “patriots” that it was up to them in order to fix the issues by standing against the Jewish population, this lead to events like Kristallnacht where businesses and homes were violated and destroyed in an attempt to make Jews fear for their lives.
Eventually when the Nazis started rounding up the Jews, not only were most of their neighbors okay with it happening, it wasn’t uncommon for them to assist in reporting and turning them in.
So you could say social engineering and propaganda over the course of years were the primary reason why the holocaust occurred, as it would face too much push back from an unprimed group that hasnt been molded over time to assess said group as “the enemy.”
But why did Hitler pick Jews? And why was tbe public so receptive?
Completely unrelated quote from Wikipedia’s article about antisemitism:
The Enlightenment adopted some anti-Judaic stereotypes, such as the juxtaposition of a supposedly nationally limited and materialistic Jewish religion of hate against a universal and idealistic Christian religion of love. In the 19th century, Christian and racist hostility toward Jews merged. Thus, Christian and racist enemies of Jews together revived the medieval ritual murder legends. Since 1900, nationalist Christians were at the same time anti-Semites, such as the Protestant church party “German Christians” of the Nazi era.
