Answer:
Hitler:
- Extermination of Jews and other minorities in concentration camps as well as in humanizing the people groups.
- Failure on his part to uphold treaties regulating German expansion peacefully.
- Creation of the Aryan race, which led to potential problems in military, economic, and other parts of life. It also destroyed the livelihood of many.
Mussolini:
- Failure to keep the other heads of state results in falling popularity as he transitions to a Facist state, which led to his eventual murder.
- Mass extermination of to-be Italy's colonies, and then afterwards failure to hold them in the onslaught of Britian's attack.
These are just some of the main points, there are definitely more, but im not too sure what you would describe as main.
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