Sophists and Reuben Langdon.

Claim 1:

Reuben defended a violent act by Trump supporters.

He didn't. Because he was actually pointing out a double standard when people justify violence for the BLM movement while condemning violence from Trump supporters.

I, myself, didn't like the way he did it. I didn't like him using that MLK's quote for it. I consider it wasn't well explained and it was ambiguous. Same goes for the video... He should have clarified to what degree he agrees with the video, or if he simply shared it as a way to question mainstream.

However, the main rebuttal still stands: he was pointing out the double standard, not defending what Trump supporters did. Something he clarified several times.

Claim 2:

BLM's objective is right and has better arguments and evidence to support it, related to police brutality; while the attack on the capitol is based on a conspiracy-theory that doesn't make sense and isn't well supported by evidence.

No shit.

Claim 3:

Violence for BLM is justified (because the objective is a right one), while violence attacking the capitol isn't justified (because its objective is wrong).

The answer to this (the first part of the claim) depends on many factors, one of them being what's your ethical system and if it could stand an ethical-consistency-check.

Let's say we are a type of consequentalists. To argument that all the looting and victims from BLM are justified, you would have to prove:

1) BLM's consequences saved more lives/has originated a better outcome than the loss from looting/victims.

2) The looting/victims were totally necessary to achieve the improvement/better outcome (basically, there was no alternative).

This is because we are far away from an obvious formal situation for basic consequentialism:

 

So good luck proving the peaceful protests, where the police itself proved police brutality is a fucking thing, weren't enough. And you still needed to fucking kill an innocent black ex cop and destroy small businesses to make society, politicians, etc., more conscious about racism/police brutality (even if they still aren't solved and we consider BLM just one step in the process).

But even leaving aside the complexity of the third claim, what's clear is that ONCE claim 1 has been counter-argumented, you either have to counter the counter-argument, or fucking concede you were wrong about Reuben. Because claim 2 and 3 aren't inherent arguments in favor to Claim 1. They are separate claims/debates.

If you use them as (fake) arguments, you are relying on a logical fallacy called moving the goal-posts.

Violence is violence, and the initial claim was about Reuben encouraging it or not... He already clarified he doesn't advocate for violence. You were wrong in this regard, period.

From here you could move on and discuss with him for claim 2 (I doubt he doesn't agree) and 3 (he doesn't agree). But regarding the first one, you were/are wrong until you don't find new evidence/counter-arguments. Implying the way he pointed out the double standard means he supports or justifies what happened to the capitol (just because the objectives of BLM and Trump supporters are different) is nonsensical. You can't deduce it from his tweets. All you can deduce is that he is against violence.

Actually even if you agree with claim 3, you would have to admit you justify violence in a very concrete situation, instead of denying it's violence simply because you think it's justified (and it isn't).