The USA genocided an entire continent under it’s current form of government, and committed and is still committing countless other atrocities. Look at what Europe did to Africa and Asia under that same form.
Bourgeois parliamentarism is a much more stable shell for colonialism than any other form of government has proven to be. Demonizing a dead form of colonialism (fascism) lets them off the hook, and never forces them to look at what their own governments are currently doing. They get to keep their chauvinist / supremacist myth about “liberal democracy” being the superior form of government, without challenging it.
I’d also like to add that hitler was very specific about his desire to emulate the US model of colonialism: and do to eastern europe, what the US had already done to its native peoples.
The only difference between lebensraum and manifest destiny, is that bourgeois democracy was far more effective at indigenous genocide than fascism was.
https://slate.com/news-and-politics/2017/03/nazi-germanys-american-dream-hitler-modeled-his-concept-of-racial-struggle-and-global-campaign-after-americas-conquest-of-native-americans.html