It doesn't skirt around the issue or go for subtlety either, just straight up states that fascism is violent oppression. I wouldn't even call it gentlemanly, just formal and direct.
I'm of two minds when it comes to chewing out someone. On one hand, I have literally torn strips off dozer operators, and can cuss with the best of them. I love well put together strings of expletives, and think the more creative you are with them, funnier they are and the more they show intellect rather than just 'huh huh fucking cunt'.
On the other side, I see the value of being overly polite but cutting. There's something personal about it. You're beautifully insulted and it feels like you disappointed your parents.
I generally tend to opt for the first option and call people slack-jawed pigeon fuckers.
Nah, it is drectly pointing out the worst parts of fascism and saying that there would be no reason to meet since Bertrand is opposed to those things. Adding in profanity, which I am a huge fan of, would not drive the point home if the direct statements are not clear already.
Now if the fascist sent a follow up asking to reconsider I would hope the reply would be "I told you to fuck off already"
Bertrand Russel had his own style, and it's complete, formal, heartfelt and true. If he tried to add a bunch of cursing to it, it would become inauthentic, just as it would if someone whose natural mode is to start cursing and punching decided to try to talk like Bertrand Russel. Everyone's got their voice.
For an equally complete, formal, heartfelt and true example which does include cursing, see: