I don't care for most adages because they're usually oversimplified, but "Two wrongs don't make a right" applies.
This has nothing to do with two wrongs. If you want someone to change their ways they must see that their current choices are hurting them and unsustainable. For alcoholics or drug addicts they generally have to hit rock bottom before they will accept that they have a problem.
That is what we're dealing with here. Trump supporters, racists, bigots... these people have mental problems. Shutting them up and making it clear their ideas will not be tolerated makes it harder for them to organize and find other like minded shit heads like themselves.
It makes it clear to future generations that their beliefs are unacceptable and disgusting.
Adding hate, resentment, etc to the world isn't helping. I don't see Robert as attempting to harm anyone with his comments. This is a political discussion forum; you don't know Robert, but you see his commentary. Maybe he'll learn from exposure to other ideas. Maybe we're all learning. Most people don't change their views quickly, if at all. I doubt people are open to learning when people are abrasive. It just continues the cycle.
I disagree to a certain extent. There is a concept in psychology called projection. It is where you assume others think the way you do. You may be more persuaded by someone who is kinder and reject someone who is abrasive. That is who you are and as a result you assume everyone else thinks the same.
But the thing that Trump supporters like about him is that he's "honest", he, "tells like it is". They like him because in their minds he has no filter. He tells you exactly what is on his mind whether it's mean or offensive or not. They belief that political correctness is a bad thing that's hurting society.
So even though nothing Trump says is true or even remotely rational the fact that he doesn't care makes them trust what he is saying more. In their minds assholes are inherently more honest. They'd have to be because if they weren't nobody would put up with them.
I call this the Sherlock Holmes effect. All throughout human literature you find characters like Holmes. Holmes was a pompous asshole. He was an arrogant jerk in many ways, but he got away with it because he was Brilliant! We see it in characters like Dr House and Tony Stark too. Assholes, jerks, but they get away with it because they're brilliant and if you want a problem solved you need them.
I submit to you that when people don't know what's true the gravitate towards a jerk because it demonstrates a level of confidence. While I might not change the mind of the person I'm being a jerk too, there are those on the sideline who find it hilarious and are more likely to assume I know what I'm talking about because of the confidence and the condescension I display.
All humans and all beings deserve well-being.
What about Nazis? Should we be nice them too? After all they just have a different political opinion right?