I went to a small meeting for my party, and at the end, one of us went on an anti-Russia and anti-Soviet rant (He's a Trotskyist). He started with saying that Russia buys gold from Sudanese rebels in exchange for Russian weapns for those rebels. I don't know if that is true although I don't necessarily doubt it, and another one of us said it's probably not only Russia giving weapons to Sudan, but US as well. He said that this proves that Russia is imperialist and that he doesn't understand why communist parties in the global south support Russia. I said to him that even though Russia has imperial ambitions and capitalist nations always move towards imperialism, I can see why global south countries want to work more with Russia since cooperation with Russia is less harmful that cooperation with the USA. I specifically said that it is choosing for a lesser evil, in order to convince him better.
Then he started talking about how Putin uses Siberian native soldiers as cannon folder to protect ethnic Russians. He then said that this is a holdover from Stalin who kept the colonial system from the Tsar were and that Central Asian and Siberian Native soldiers were sent to the front first in order to protect Russians. He said that Soviet Union was a colonial nation as well for the Russians and Belarussians and that the Soviet Union fell because of this colonisation and that Gorbachov was the first one who tried to correct it.
After that the other member said that it's hard to convince others when there are not many examples of actually socialism. She then named Cuba as a dictatorship, and I called her out and said it was not. Luckily she was receptive. The trotskyist defended me as well saying that Cuba 'is not as bad' and he mentioned that Cuba has a lot of international solidarity because they for example sent doctors to Northern Italy during covid. But he didn't mention that international solidarity for Cuba also means that they support Russia lol. Then we started talking about Che, and he said that Che wanted to become a minister in Cuba but was forced to leave Cuba by the Soviet Union, because they didn't like him. I said that it was hard to believe and that I didn't hear about it. He forgot where he got that from and said that not many people know about it.
I definitely held back a lot, and should've gone harder sometimes, but it's harder when the other person brings up so much random wild stuff that you don't know how to start to refute it.
What are some strategies for the next time?
Oh my, so so tiresome.
This is the thing. How can you possibly be prepared for some obscure non-falsifiable crap like this plucked from a point in history? Even if you were, do you think this ranter is open to being talked down and reasoned with? They've decided a priori what club they're in and everything will be reasoned to justify that decision. They haven't built up an opinion from first principles.
If you're not communicating with a shared vocabulary then the conversation is already doomed. This leaves you with the option of arguing your definition and explaining why the characterisation doesn't apply, which is time consuming, tiring and unlikely to succeed. Or asking them to explain their definition... but anyway, why? Even if we're using Trotsky's simplistic idea of "imperialism", so what? Nobody was ever holding Russia up as the apotheosis of socialism. The slurs are irrelevant. The point of critical support of Russia is with its existence as a massive thorn in the side of western imperialism, an ally of socialist China (oh great here's another leg of the fractal to descend)... etc.
Isn't it always funny that no existing socialism is ever good enough?
While I don't recommend taking part in these conversations in real life, if you must, one simple thing you can try is to make sure you don't accept any homework. They're the one doing the ranting, let them do all the heavy lifting and then reductio ad the inevitable absurdum.
"Hold up, what do you mean by 'imperialism' there? Uh huh, okay. So the USA and Russia, they're... uh... the same thing to you. Okaay."
"So a dictatorship? Do you think they should let the USA take them over so they can have the democracy?"
Okay mr random history expert. "Is there a Trotskyist state in history we should all aspire to match then? No, that's a shame. So we just have ideal theoretical concepts that we have to live up to. Okay. Why do you think it's never worked out. Ah Stalin again, I see. He's been gone a long time though..."
In my experience Trots just tend to try to weaponise leftist terms to use them as mindless angry slurs. These are all denial of service attacks on your mind. The old Brandolini's law applies.
The amount of energy needed to refute bullshit is an order of magnitude bigger than that needed to produce it.
This is usually different than anarchists who will just repeat a cheesy thought terminating cliché that they think is profound, but doesn't stand up to scrutiny. At least Trots have some kind of theory, even if it's a cargo cult.
Trying to beat these people with facts and logic will drain and frustrate you. And if you get angry you lose. You need to go in with very low expectations. You may just need to remind yourself why you have any camaraderie with these people at all. If there's some value in it, then steer everything towards that, don't try to convert, it's very unlikely to succeed. You can just let them blow off steam and then, do a "Okay, so anyway, about the thing we're all here for..." on them.
Online in text form is a place where honest discussion of these things can be reasonably had, even then it's rare. Real life conversations are just a game of who's the best at berating and interrupting and appealing to the crowd.
This right here is the answer OP.