> If they deny that they are nazis or fascists, well, that just proves they are nazis or fascists. (...) used by so-called anti-fascists to legitimise physical assault on ideological opponents

That's plain bullshit. A few creampies thrown, an actual white supremacist ideologue getting punched in the face, and a bunch of popular self-defense groups does not equate with "legitimizing assault". I mean punching a nazi in the face is a thing, but it's neither a programme nor generalized and is not a threat to their health. When was the last time you saw antifascists attack defenseless people or kill random people? Yeah that's what i thought only nazis and other deranged reactionaries do that.

> those who deny they are racist thereby confirm their racism

I think any serious anti-racist would recognize to be racist as well, not in ideal but in practice. Political anti-racism recognizes that we were not raised into a void, but in profoundly racist societies. Acknowledging one's racist education and feelings (to deconstruct them) is a must. And if you believe only white people can be racist, or that white people (in our western societies) can be victims of racism, you're probably missing the point and should educate yourself on these topics.

Approaching the topic from a moral judgement perspective leads oneself to overlook their own shortcomings and just point the finger at somebody else, which is not helping. Antiracism and antifascism are political struggles to tip the balance of powers in the world, not mental frameworks to absolve oneself from wrongthinking. We'll probably agree that the morally-superior liberal (as in, content with the status quo and not advocating for social revolution) Twitter police is not helping the situation for anyone.

> Honest question: would you be more inclined to trust a person or collective declaring themselves to be, say, anti-communist than one declaring not to be communist?

I think i'd be more trustful of any anti-something in general, because people usually have a good idea with what they don't want. For a counter-example, most people who label themselves communist in fact desire a dictatorship of the proletariat, which in marxist discourse is not communism (supposedly just a transitional step).

"Anti-communist" people, on the other hand, are very clear that they don't want mutual aid and self-organization, which are borderline characteristics of fascism. Hitler was famously placed in power by the industry owners leveraging anticommunist/anti-union rhetoric, while Mussolini argued that fascism should better be called "corporatism" because it represents a merger of corporate and State power. All this is well documented in history, and you can find a TLDR in the Fascism Inc documentary: https://www.youtube.com/watch?v=c01NN9zvTe0

> "anti-fascists" (who more often than not are all too happy to use the same tactics as the original brownshirts used to spread their ideology)

Oh, really? Antifascists don't have leaders and discipline, receive paramilitary training and organize to attack and kill random people for their religion, culture, or sexuality. To those people who can't see the difference, maybe this will make you think, or at least laugh: https://ttm.sh/trk.jpg