I get flustered and come off brash. In crude terms, I can be an asshole. But it comes from a good place, out of compassion, I believe.
I so often talk to people who have set their minds to an idea, and they spend all their energies trying to reinforce those ideas, even when logic and all sense defies it. I try, even if I fail, to present them with reasons why they may be wrong. And I eagerly await their counterpoint because I don't believe that I'm right just because I believe something. I humor myself with a paraphrase Socrates (a la Plato) that I know more than most because I know that I know nothing. That's why I spend so much of my personal time looking into facts and figures; so when I see misinformation or plain ignorance, I have the opportunity to bring these people toward their own knowledge.
And I possibly get more flustered with someone of higher intelligence and education, as I hold them to a higher standard than I do most. I know they have the ability and capability to reach their own conclusions based on logic, reasoning, research, and facts. I recognize that may be unfair, but as someone once said, it may be "unfair, but not unjust." (Sidney Morgenbesser said this about the police hitting him while protesting the Vietnam war. It was unfair that he was hit, but not unjust as they hit everyone.)
More to the point, when I see someone of their obvious ability make such statements (as "Trump is clearly racist") but this conclusion appears based on bad data (in my opinion, of course), I feel obligated to challenge that belief. And too often, the response is self-reinforcing or attempts to twist logic to reinforce the original idea. You see, if I believed they lacked the ability to provide point-counterpoint, I wouldn't confront their ideas with as much vehemence.
For instance, when I pointed out the logical fallacy of "Trump's a racist", they do not immediately provide any evidence of their own. They often attack the logical fallacy. While I give them points for style, they get no credit for addressing the issue. When they do provide evidence, they come from a place of "My assumption is Trump's a racist. From that we can prove..." That is bad form and horrible logic.
So, if they say, "supporting Trump is to support racism," they have already implied that Trump himself is racist and will promulgate racist ideology. I then am forced to go through the assumed litany of charges against Trump which I assume are their arguments (since they did not provide their own). The charge of Trump's racism often stems from his position on illegal immigration. So, I address that his position is little different than those of Bill Clinton 20 years ago. Also, Trump's position on Middle Eastern refugees is often a source of accusation; so I addressed that. And so on. If I can show that Trumps political positions are not racist nor motivated by racism, then the support of those who are racist will have no sway over his policies.
If they do not present their own argument, I have to assume their arguments for them. That's not the way I like to have discussions. But if they only argue semantics and not facts, I have little other choice.
And I will not apologize for my brash tone or my offensive manner. I want them to get upset. I want them to convince me. I want them to bring their best reason and logic. But most of all, I want facts. And if they cannot provide those, I will continue to challenge their assertions.