I'm certainly not defending the Nazis here. I'm cherry picking because someone claimed there were no cherries (socialists) in that bowl of grapes (nationalists) and cherries. So I'm pointing out the socialists.

The role of the left in the rise of the worst governments of the twentieth century should be remembered, so that nothing like Hitler ever happens again.

Many horrible governments start with promises of equality and a humane society (not the Nazis, who promised revenge, but certainly the communists), because that much concentrated power is a catastrophe waiting to happen. A government big enough to give equality is also powerful enough to impose tyranny, as we saw far too many times in the 20th century.

Even the Nazis only rose to power because of the horrible mistreatment imposed on Germany by the Treaty of Versailles. Germans saw themselves as the oppressed people.