I am going to put the tl;dr right at the top and say that I completely second Greeny's advice: present the question if you must, but do not provide the answer.
That said, there are quite a few things you've said which jump out at me in a very bad way.
writing about an issue you care about, and feel a lot of fiery passion for,
intended to bring a certain issue to light
a genuine attempt to educate people
and it's a hot button issue for me--to be more specific, there's one aspect of the issue that sets me off and makes me angry, and I want to explain why this attitude is NOT okay
What I want is for people to recognize when this attitude occurs and realize it's not okay.
I know what the message I'm aiming for is, but it’s important for the reader to understand it
I can understand the underlying causes of prejudice and why some people are so easily influenced by it. And yes, it’s true that often, they’re just simply unaware of just how truly awful the issue really is and only know the version their parents brought them up with.
In this particular story, dealing with prejudice directly is the right way to do it.
those who genuinely believe there's nothing wrong with denying minorities equal rights and don't even see it that way
Firstly, I have bolded several of your statements to highlight a prevalent attitude in your words:
condescension. You seem to be under the impression that you are
particularly enlightened about a subject and that the
only reason others don't see it your way is because
they are simply ignorant. You are putting yourself on a rather towering pedestal, imagining yourself to be stepping down from on high to
educate the sorry unwashed masses, and I can guarantee you that every single reader you reach
is going to detect that. Whatever this issue is, you will not do it any justice by carrying an attitude of
talking down to people in the way that you are perceiving them in your mind.
Even non-contrarians will have their instinctive defenses activated when they detect that someone is attempting to influence them,
even if it's in a direction they are already headed for anyway. This blowback is enough of a challenge in direct, open debate. When you try to weave your message into a story, you take on the additional challenge of appearing to make an indirect attempt to manipulate your audience's opinion, and they will pick up on that the moment you start winding up for it. You are likely to insult your reader by presuming to mentor or teach them, rather than simply entertain or tell a tale.
I can't speak to the issue itself since you want to keep it secret, but I can say that I have no doubt you will fail in influencing your audience if you condescend to them. And if you view your audience as ignorant and yourself as enlightened, I don't see how you will manage to avoid falling into that pit.
Far be it from me to stick to vagaries, I'll provide an example from a project I became
very briefly involved in a couple of years ago. The project lead lacked writers for his story, and when I volunteered to write a few scenes for him, I quickly learned why. One of the scenes he wanted written involved the protagonist and his trans love interest; they were to be walking down the street when they were to suddenly become accosted by a group of half-a-dozen homo/trans-phobes, who would spout a few cookie-cutter trans/homo-phobic phrases, then assault the protagonist's love interest. At this point, the protagonist would then soundly defeat the bad, evil -phobes, then stand triumphantly over them to declare that "you just got your ass kicked by a faggot."
Never mind that the characters have no reason to be strolling down the street (there wasn't even an idea of them being on a date or anything, it was just "they're walking down the street, when suddenly..."), never mind that the -phobes could not possibly have been able to tell just from looking that the protagonist and his love interest weren't just a typical hetero couple, never mind the fact that your unarmed and untrained protagonist is meant to overcome six-to-one odds (the love interest was very distinctly a noncombatant) without the advantage of surprise or initiative, and never mind the enormous improbability of this entire event taking place completely uninterrupted in public and in broad daylight (nobody sees or calls the cops or anything?); all that mattered was that
the project lead wanted to have an anti-trans/homo-phobic message, and this scene was the way he wanted it done.
How do you think that project lead reacted when I presented the above issues to him? How do you think he reacted when I suggested that the audience might see the whole scene as a heavy-handed attempt to preach to them? And not only that, it was preaching done in the form of Aesop's The Lion and The Statue - an argument solely consisting of the depiction of a strawman being defeated. If your answer was "he called you a bigot and shitcanned you from the project," then you were absolutely correct.
All of this, because he was
so excessively passionate about a political topic that he looked down on others and brooked absolutely no cross-examination or analysis of his methods in presenting that topic in a story. The issue was so important to him that he completely forgot that
you still have to be attentive to all the things you normally must be attentive to if you want to create a quality story. Apparently the nobility of the message was meant to be enough to carry it.
That project? It's dead in the water, now.
I do not recommend sacrificing a story on the altar of a noble cause. The light of righteous indignation is most blinding to the one who holds it closest to his heart.