[rustbucket]

Perhaps this 1920 letter of Lenin will help. It identifies right wing socialists.

Lenin 1920 letter defining right wing socialists

[stormhill]

Very enlightening.
This shows that the left/right discussion has been from the perspective of revolutionary communists which is irrelevant, not from the center/right American context.

To paraphrase the old joke: "To you he's a left winger and to me he's a left winger; but to a left winger is he a left winger?"

Anyone who sees this and denies the Nazis were leftists is either stupid or mendacious.