After World War II, the Nazi government of Germany was defeated and put on trial for war crimes. The use of Nazi symbols, such as the swastika and the Nazi flag, was banned in Germany as a way to prevent the spread of Nazi ideology and avoid the rise of another authoritarian regime.
In other countries, the legality of owning or displaying Nazi symbols varies. However, most countries have laws that prohibit displaying or using such symbols in public places, such as schools, government buildings, and public events.
While some argue that the display of Nazi symbols falls under free speech rights, it is often seen as a disrespectful and hurtful act to survivors of the Holocaust and their families. Therefore, the use of Nazi symbols is generally discouraged and condemned by society.