At that time, the mainstream thought of Nazi Germany was that "except the German nation, all other nations are inferior." The first class is Germany, the second class is a western nation except Germany, the third class is an oriental nation, and the lowest class is a Jew. "The Nazis pursued the law of the jungle in the animal kingdom and Darwin's view of' survival of the fittest'. So it is not difficult to understand why Jews should be slaughtered. Do you have any objection to us humans eating pork and fish every day? Do you feel guilty about it? Of course you won't. You are an advanced animal, eating these low-level creatures is nothing! ! Therefore, in Nazi's view, they won't feel guilty for killing Jews. To them, you are pork and fish, and they are people. Of course, why the Nazis had such abnormal thoughts is another story. There is also a saying that when Hitler was young, his mother was seriously ill and went to see a Jewish doctor, but because her family was poor, the doctor refused to see her, which eventually led to her death. Young Hitler always bears a grudge against Jews. PS。 If you want to explore and understand Hitler's thoughts by yourself, you can read a book called Mein Kampf written by Hitler before his death.